It’s worthy of one of Willy the chimp’s dreams. You can imagine Anthony Browne, Willy’s creator, sitting in his armchair during a quiet moment, smiling contentedly to himself, as Willy does: “It’s as if I am having a secret affair. I can’t tell anybody about it but every time I think about it, it gives me a warm feeling inside.” For Browne the dream has become reality - not an illicit relationship but winning the Hans Anderson award for a lifetime of achievement in illustration. He is the first Brit since Eleanor Farjeon to have won an Andersen award from the International Board on Books for the Young.

Browne, who has created 32 children’s books over the past 25 years and is particularly celebrated for his Willy books - stories about a sensitive, under-confident primate - picked up the award in Bologna at the international children’s book fair earlier this year. The Hans Andersen is perhaps the most prestigious award an illustrator can receive, yet it attracts little media coverage and is not particularly well known - even in the book trade. This, says Browne, probably has something to do with both its being a non-UK award and the status of illustration in this country, which he believes reveals much about our attitudes to visual literacy. He has twice won both the Kurt Maschler Award and the Kate Greenaway Medal, but still feels that the artist in the world of books is a second-class citizen, that the real accolades fall to writers because as a society we are comfortable with words, not pictures.

His own illustrations are full of visual games and challenges, their sharp, graphic clarity describing an enigmatic surrealism. They are playful and witty, yet discomfiting at the same time. Indeed, some adults fret about the disquieting messages within the frames and argue that Browne’s stark and highly charged pages, full of emotional complexity and art-historical references, are not suitable for the young. But he finds that children enjoy his visual games.

“Children will notice the hidden pig-face in the door handle - they are still in touch with that visual reading - but I do think they are encouraged to move away from that as they get older.”

Rich in their references to great artworks, Browne’s illustrations are especially indebted to 20th-century surrealism - Magritte and Dali most of all. But there are also allusions to Picasso, Rousseau and Giorgio de Chirico. They also have some of the zaniness of English pop art. From his lifelong attraction to surrealism he has absorbed the wit and visual playfulness of the movement, but also the darker sense of a world where nothing can be taken for granted, where the ground shifts constantly.

Perhaps this has something to do with the fact that at the age of 17 he saw his father die suddenly from a heart attack, which inevitably transformed his world. But his fascination with surrealism began before that when his art teacher at school introduced him to the work of Dali - “It felt like coming home” - and even before that when he first read Alice in Wonderland. He recalls drawing surrealist-style pictures as a small child.

“I had this special character called Big Dum Tackle whom I used to draw when I was four or five and he would do weird things like fly up to heaven and knock on the door and ask Jesus if he wanted to come out to play.”

At last week’s Reading Pictures conference at Homerton College, Cambridge, he used a childhood drawing to open a survey of his life’s work: from medical illustration (“I had to draw operations in progress, and learned how to tell the story of the operation, which looks like bits of stuff and blunt instruments when you’re watching it”) through his first gorillas for Gordon Fraser greetings cards to picture books which explored facets of fatherhood, such as Gorilla, Hansel and Gretel and King Kong. He had been close to his own father, but found that those in his books emerged as more distant and ambiguous “although this started to change when I became a father myself”. The father in My Dad, published this year by Doubleday, is unambiguously loving.

Surrealism has continued to be his vehicle for expressing all those uncertainties about life that one experiences as a child and a teenager. Browne encapsulates with sharp wit and understanding the feeling that everyone else is more knowing, more powerful, more able. He gives shape to the monsters that people our thoughts and our bedroom wallpaper; our deepest vulnerability.

He has always been open about borrowing the visual grammar of other artists. As well as enriching his own books, he feels that this practice helps children to become familiar with great and interesting paintings of the past. In his latest book, Willy’s Pictures (Walker Books pound;10.99), Willy is an artist who re-interprets his favourite pictures such as Brueghel’s “Tower of Babel” (an elaborate sandcastle about to be washed away by the sea); Edward Hopper’s “Early Sunday Morning” (in which Willy takes his persecutor Buster Nose for a walk on a lead past a parade of shuttered shops); Raphael’s “Saint George and the Dragon” (in which he vanquishes Buster once and for all). Browne wants children to be encouraged to interpret the pictures for themselves. However, his homages to surrealism have brought him into conflict with the Magritte estate, which argued that some of the pictures in his 1997 book Willy the Dreamer (Walker Books pound;9.99) infringed copyright. Browne had to recreate the entire book for a forthcoming new edition and was left feeling bruised. The irony, he says, is that he was only doing what Magritte himself did. “At first we didn’t think the Magritte estate could do this but after consulting specialist art lawyers, Walker was told that they could. It’s something to do with reproducing a substantial part of the painting. But artists have been doing this throughout history. Magritte himself did it with the work of Manet and David. In one David painting he did no more than substitute people with a coffin. I had to repaint a lot of paintings in Willy the Dreamer, painting out all the direct references, not only to Magritte but also to de Chirico and Dali. I experienced a lot of emotions - anger, lack of confidence - but overall I felt very depressed. It was as if somebody had accused me of cheating in publicI I know I wasn’t cheating. I was doing what painters have been doing throughout the ages, but it made no difference.”

The full implication of the Magritte case was brought home when Walker was in the process of publishing Willy’s Pictures. The publisher approached the estates of Grant Wood, Chagall, Otto Dix, Picasso and Munch and were told that their paintings could not be used in this way. Browne was appalled.

“The first painting I wanted to use was Grant Wood’s ‘American Gothic’ (an influential work of American regional realism). I had actually called in at the Chicago Art Institute on one trip to the US to look at an exhibition, which was a dedication to the painting and its influence - showing all the different ways it had been referred to in film and advertising.” But Wood’s estate said no. Only the Edward Hopper estate approved, hence the inclusion of “Early Sunday Morning” in Willy’s Pictures alongside older works not subject to copyright. Again the book had to be reworked.

Perhaps the most painful part of this episode is that these last two Willy books were Browne’s most personal works, both a series of images not bound by any story, in which his most subconscious thoughts could find expression. He is now having to reconsider how he will make books in the future. Will this mean the end of Willy?

On the final page of Willy’s Pictures, it does seem as if an era is drawing to a close. A mask of Willy’s face is left on the artist’s desk, his sweater hung over the chair as the artist walks out. Maybe the whole enterprise has got too close for comfort. But Browne feels he can never be categoric about Willy. “I don’t want to be known as the man who does those Willy books, or even as the man who paints gorillas. In Willy the Dreamer, the last picture shows Willy sort of melting into his armchair. Is he real, or just a dream? That was the question readers were left with. But he still came back.”

The gorillas returned after a break in Voices in the Park (Doubleday 1998), which offers accounts of a visit to the park through the eyes of four very different people. Browne says: “I lost confidence in Voices in the Park because at first it was a book about specific characters. But the people remained stereotypes, cliched, and I couldn’t get away from that. It was only when I gave the people gorilla heads that it began to work. Somehow that lifted the book, gave it an edge, made it funny but strange.”

The books are not principally about gorillas, he points out, but rather about imprisonment, about people being trapped in modes of behaviour like gorillas in a zoo. They attempt to express something about the universality of our experiences: “A lot of Willy’s success is due to the fact that so many people can identify with him. If I had made him a specific boy aged six, 16 or 56 he wouldn’t have been so popular.” Indeed Willy has found popularity all over the world.

In Browne’s studio in the leafy garden of his home in Kent, there lies a miniature Willy, complete with Fair Isle sweater and beautiful little leather shoes. It was given to him by an old Colombian woman who visited an exhibition of his work put on by his Mexican publishers. “Maybe that’s also why I won the Andersen medal, because there is nothing specifically English about Willy,” he adds.

Browne is now contemplating a book of fairy tales, but he is anxious not to add yet another glossy commercial volume to the existing mountain of illustrated retellings. One suspects, given his chilling yet redemptive interpretations of fairy tales in Hansel and Gretel and The Tunnel, that this would be far from the case. Browne has rarely compromised to suit the market.

It wasn’t until his seventh book (Gorilla in 1983) that he began to sell well. “But I’ve been lucky. I have managed to resist the pressure to become more cute or cosy and nobody has ever asked me to do things differently.” Thank God for that.

Anthony Browne will take part in a series of talks at the National Gallery early next year to support Quentin Blake’s Tell Me a Picture exhibition (see diary page 15).