Professor Capp said impeachment in Britain had largely been used as "a means of attacking unpopular ministers" put into office by the King - especially in the 17th century.

He proved an unpopular minister with Labour backbenchers, and was attacked by those on the left of the party.

Bate defended the piece as an attempt to show that the unpopular prime minister was exploiting his daughter for political gain.

But the bigger-than-expected victories for the PP will increase pressure on the unpopular prime minister to step aside before his term is up in March 2012.

Two days after Henry's coronation, he arrested his father's two most unpopular ministers, Sir Richard Empson and Edmund Dudley.

Mulroney left office as one of the most (and according to Campbell, the most) unpopular prime ministers since opinion polling began in the 1940s.

A survey conducted by Swedish radio news in November 2008 among local party chairman for the four Alliance parties, showed that Tolgfors was the most unpopular minister in the government.

He initially tried to bolster his government by offering to appoint some prominent Conservative rebels and sacrifice some unpopular ministers, but demands for an all-party coalition government grew louder.

Sacking Samir Rifai, the unpopular prime minister, may seem a major concession.

This is the sequence we're getting used to," he said, referring to previous announcements of arrests of corrupt regimists, or the removal of unpopular ministers.