The row broke as the author of Not a Penny More, Not a Penny Less wrote to some 4,000 of the capital's schools of his belief that they should have more resources.
The mailshot, which marks a new phase in open campaigning for the position, is not covered by rules on election expenditure because it happened long before any election is due to be called.
The letter, which was sent to the chair of governors of most of London's schools, was accompanied by a copy of the peer's unofficial manifesto, a pamphlet entitled A Better Deal for London.
He appeals to the governors as people "who understand the problems of London schools", and argues: "It is wrong that London pays so much and gets too little back. I believe we need a crusade for fairness for London."
The mailing, thought to have cost around pounds 4,000, carefully avoids any mention of his candidature for mayor although he is front-runner among Tories.
On Thursday, London's voters will be asked to approve the Government's plans to establish a London mayor and an elected strategic authority for London.
A Labour spokesman said: "We see it as an unwelcome development for campaigning for an individual to use their vast personal wealth to distribute propaganda in this way. We believe his intention is to circumvent the law."
But an Archer aide, Stephan Shakespeare, defended the operation: "Jeffrey is a very active parliamentarian and has every right to communicate with people on an issue that concerns him."
While Lord Archer is the Tory activists' choice for their party's nomination, some of the leadership are cool about the candidature of such a controversial figure. Labour has a similar problem with Ken Livingstone, former GLC leader.
The contenders, page 4Reuse content