David Cameron has been considering fixed-term parliaments for at least three years, aides said yesterday.

The Tory leader did not take advice from his panel of constitutional experts before the announcement, they insisted. Instead his adviser, Steve Hilton, and policy chief, Oliver Letwin, helped to craft what the party billed as a “keynote speech”.

In seeking to wrest back the initiative over political reform Mr Cameron drew heavily on policies already adopted after being recommended by a Democracy Task Force, chaired by Ken Clarke. Proposals to give MPs more independence including the election of select committee chairman and to reduce whipping, for example, were recommended by the task force last year.

Mr Cameron’s statement that he was “seriously considering” introducing fixed-term parliament broke fresh ground, however. His aides said that he had drawn on his experience and judgment rather than taking soundings from the group, which includes the former Cabinet Secretary Lord Butler of Brockwell and Sir Christopher Foster, an academic and former government adviser.

Another member of the group, Laura Sandys, chair of the open-Democracy think-tank, said that it had briefly discussed the option of fixed-term parliaments in the course of a report on curbing executive power published last year. It had failed to attract sufficient support to be included in the recommendations, however. Ms Sandys said that the group had not considered any proposals on electoral reform since it was set up in 2006. Neither did the option on fixed-term parliament appear on a list of Conservative proposals to restore trust in politics supplied to The Times on Friday.

One of Mr Cameron’s aides insisted that he had been toying with the idea since becoming Tory leader, however. “David’s been thinking about this for a while. It fits into everything we’ve been saying.”

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