The company which is favourite to run the marking of next year's standard assessment tests argued last year for them to be scrapped in their current form, The TES can reveal.
Edexcel, the only one of England's three exam boards not to have ruled itself out of the race to organise the Sats in 2009, argued against the tests in evidence to a Parliamentary inquiry.
It said teachers should conduct their own assessments of pupils' performance, replacing the national system of externally-marked tests.
Edexcel's position will put further pressure on the Government, which is urgently seeking a replacement for sacked marking contractor ETS Europe with next year's tests just nine months away.
Teacher unions have questioned whether a new company can be put in place in time for the tests to run smoothly next year, and have called for the Government to use the opportunity to scrap the Sats.
ETS Europe's contract was terminated last week, after only one year of a five-year, pound;156 million deal to mark the tests. It followed a shambolic summer in which tens of thousands of pupils have still not received their results.
Two weeks ago, The TES disclosed how the other two leading exam boards, AQA and OCR, were not interested in stepping in to run the tests.
But now it has emerged that the only one that refused to rule itself out of taking on the contract, Edexcel, which ran the marking process from 2005 to 2007, argued in evidence to the Commons education and skills select committee inquiry into assessment last summer that Sats were being asked to fulfil too many functions. "National testing has too many purposes attributed on one test experience," it said.
Currently, the tests are used to check national education standards; for school-by-school accountability through league tables and Government targets; and, theoretically, as guides to help children improve.
In its evidence, Edexcel said that a small sample of pupils, rather than entire year groups, should be tested to give information on national education standards.
It said that for school-by-school accountability, teachers should conduct their own assessments, which would be moderated to give reliable information on standards. Answering the question "Should the system of national tests be changed?", Edexcel replied: "On balance, yes."
The revelation comes as the Qualifications and Curriculum Authority prepares to put the new contract out to tender next month, eight months before the next tests. By contrast, the bidding process for the 2008 Sats began as long ago as spring 2006, or two years in advance, QCA documents show.
John Dunford, general secretary of the Association of School and College Leaders, said: "This is an incredibly short time in which to appoint a new provider, prepare the infrastructure and recruit markers."
Another contender has emerged to run the contract: Capita, the specialist outsourcing company. The firm said this week that it made an unsuccessful bid for the contract that ETS Europe won. It refused to say whether it would bid again.
Another option could be for the marking to be run by the QCA. But as it is preparing the contract for tender, this is unlikely.
MARKERS' LISTS STOLEN
A laptop with the names, addresses and telephone numbers of 17,052 markers was stolen last year. The revelation, found in the Department for Children, Schools and Families accounts, comes after a disastrous summer for the testing system and ETS, the company that ran it.
Names, addresses, telephone numbers, dates of birth and marking ratings were stored on the hard disk of the laptop, belonging to the Qualifications and Curriculum Authority. It was taken on April 18 this year, as ETS prepared for its first year of running the tests.
The laptop was encrypted and a statement in the department's accounts says: "the risk of the data held on the laptop being accessed by an unauthorised user is extremely low". But one marker told The TES that she had not been informed. "I am quite appalled. I knew nothing of this," she said.
The theft was reported to the Information Commissioner. It is not clear whether the incident had an impact on the tests.