As Conservative backbench sentiment moved increasingly against Mr Mellor in the run-up to the Conservative Party conference, and in the wake of the Government's humiliation over the pound, 10 Downing Street said that Mr Major remained firmly behind his minister.
Mr Mellor had not referred the gift upwards to the Prime Minister 'because there was no obligation', the sources said. There was no difficulty in ministers accepting gifts worth several hundred pounds 'as long as they are sure in their own mind that they will not be compromised'.
That appeared to contrast with Whitehall's ministerial rule book, Questions of Procedure for Ministers, which states that it is 'a well- established and recognised rule' that no minister or member of their family 'should accept gifts, hospitality or services from anyone which would, or might appear to, place him or her under an obligation'.
The rules add: 'This is primarily a matter which must be left to the good sense of ministers. But any minister in doubt or difficulty over this should seek the Prime Minister's guidance.'
Downing Street sources dismissed suggestions that the gift, from an independent film-maker to the then Minister for the Arts, might be covered by the appearance of an obligation as 'tenuous'. Mr Mellor had been clear in his own mind that the gift did not compromise him and 'there was no need for him to refer it upwards'.
Bryan Gould, Labour's heritage spokesman, wrote to the Prime Minister yesterday to say that the gifts 'were apparently made in the context of a relationship which might give rise to some concern about influence that might have been brought to bear'. He formally asked the Prime Minister whether Mr Mellor reported the gift to him, 'and was your approval obtained? If not, what do you propose to do about it?'.
Yesterday, Mr Mellor denied newspaper speculation that he was about to resign, telling reporters 'definitely not' as he arrived for an Arts Council lunch.
But sentiment is turning against Mr Mellor among some backbenchers, one saying that the party could not afford two damaged Cabinet ministers appearing before the party conference in a fortnight's time.