A report in yesterday's Sunday Telegraph said William Hague had ignored advice from Yellow M to appeal to "floating" voters and had instead opted to concentrate on one issue -- the single currency.
Yellow M and private Tory pollsters, ICM, were said to be unhappy with two poster ideas concentrating on opposition to Europe. One of the posters, currently on display in Scotland, shows a map of Europe with England joined to Northern France and the slogan "Lose the Pound. Lose our independence".
The second poster, due to be unveiled in the final weeks of the campaign has the slogan "In Europe" written in Labour red and the words "Not run by Europe" in Tory blue underneath.
Both Yellow M and ICM are said to be concerned with the Tories' lack of concentration on mainstream issues such as health and education -- traditionally top of voters' priorities in opinion polls.
According to Conservative central office said that the reports were "complete and utter fiction" and added that the agency had drawn up the posters.
On Saturday Ronnie Duncan, a director of Yellow M, said the reports were nonsense: "The brief was determined by the politicians a long time ago. I am happy with it and it is working."
Conservative Party leader William Hague also denied reports of a rift. Speaking on Radio 4's The World this Weekend, he said: "I can tell you there is no disagreement within the Conservative party about our approach to this election."