David Cameron has insisted his controversial election strategist Lynton Crosby does not intervene on policy issues, but repeatedly refused to say whether he had discussed the issue of tobacco packaging with him.
The Prime Minister has come under sustained pressure to say whether Mr Crosby, whose lobbying company has worked for tobacco giant Philip Morris, had spoken to him about shelving the plan for cigarettes to be sold in plain packaging.
He described Mr Crosby as a "very talented political consultant" but stressed "he has not intervened in any way on this or indeed on other issues".
The Prime Minister, appearing on BBC1's Andrew Marr Show, claimed it was a "media invention" and a "red herring" to suggest that Mr Crosby had any involvement in the decision.
Mr Cameron also stressed that he did not rule out pushing ahead with the plain packaging policy in the future and claimed the Government had been "very tough" on tobacco.
Broadcaster Marr, who returned to viewers' screens last week after a stroke, pressed the Prime Minister on the issue of whether he had talked to Mr Crosby about the policy but Mr Cameron repeatedly side-stepped the question to say only that his strategist had not "intervened".
Mr Cameron said Mr Crosby was "advising the Conservative Party on how to take on Labour, how to make a political argument, how to prepare for the next campaign" but "he's not advising us on policy or on issues ... and he doesn't intervene in those".
The Prime Minister said "we haven't actually changed our policy" on plain packaging and "there are merits" for the move.
But he added: "We need more evidence, we need greater legal certainty. We're not going ahead with it right now, but I certainly don't rule it out for the future. So the whole thing actually from start to finish has been something of a media invention. So, you know, he hasn't intervened. It would be wrong for him to intervene in any way."
Asked a second and third time if he had talked to Mr Crosby about the policy, Mr Cameron again stuck to the line that the Australian lobbyist had not intervened. Marr said that was "not quite an answer to the question I asked", but the Prime Minister told him: "Well, that's the answer that you are getting."