Britain's William Hague announced his resignation as foreign secretary to become leader of the lower house of parliament on Monday, part of a reshuffle of the Conservative-led government.

"Tonight I am standing down as Foreign Secretary after four years to serve as Leader of the House of Commons," Hague wrote on Twitter.

Hague said he would not stand in the May 2015 general election in order "to embark on many other things I have always wanted to do."

Prime Minister David Cameron is expected to reveal several other changes within his government in a reshuffle to prepare for the election.

The leader of the House of Commons is a minister who organises business in the lower house and works closely with the government's chief whip.

British politician Kenneth Clarke, a veteran pro-EU Conservative, also resigned from his post as minister without portfolio on Monday.