Masha Bell, a former teacher and author of books on spelling, said it was unfair to compare the achievements of English-speaking children with those of other countries because of irregularities in English spelling.
"Pupils in this country start their school lives with a disadvantage, and that is the orthography of the English language," she said.
"The spelling is unpredictable and illogical and it is time that we seriously considered reforming the way some words are spelt. We try to teach phonics but the truth is many words have to be learned by sight and memory because phonetic rules don't apply."
Ms Bell, who has written a book called Understanding English spelling and speaks six languages fluently has submitted written evidence to the Commons education select committee, which is looking at the teaching of reading in primary schools.
She has compiled a list of 80 words which she believes are impossible for young children to decode phonetically because they are not written as they are said.
They include words such as book, should and push which have the same sound but are spelt differently. She is also concerned about "silent" letters in words such as write and believe, and words such as brother and another where the "o" sounds like a "u".
Overall, however, Ms Bell believes there are more than 2,000 common words which pose problems for young readers, and foreigners learning English.
She said: "In virtually all other European languages identical letters spell identical sounds and learning to read is therefore much easier. This makes it clear that it is inappropriate to look to other countries for guidance on the teaching of reading in the UK."
She added that the irregular spelling was the reason why "poor literacy standards are common to all English-speaking countries".
Barry Sheerman, chairman of the select committee, said: "Ms Bell may well have a point, but the committee won't be jumping to any fast conclusions.
This area is fraught with ideological problems, which we did not dream of when we began the inquiry."