OTTAWA — Prime Minister Stephen Harper has chosen a longtime conservative crusader for lower taxes to be his new director of communications.

John Williamson is to be named today to the post, filling a hole in Harper's team created this summer by the departure of two top communications advisers.

Williamson will take over the dual roles previously handled by Kory Teneycke and Carolyn Stewart Olsen.

Teneycke was communications director and Stewart Olsen was director of strategic communications.

Olsen is expected to be named to the Senate today.

Until last year, Williamson was the national director of the Canadian Taxpayers Federation and a vocal opponent of tax increases and waste of taxpayers' dollars.

He left the federation to undertake a masters degree in economic history at the London School of Economics.

Although the federation bills itself as non-partisan, Williamson is a longtime conservative and Harper loyalist.

He was co-chair of the campaign to draft Harper for the leadership of the Canadian Alliance, the Conservative party's predecessor, in 2001, and subsequently became Harper's leadership campaign spokesman.

Williamson steps into his new role with the threat of a fall election looming over Harper's minority government.