Deputy Prime Minister Nick Clegg has vowed that the coalition Government will stay the course and would not crumble under pressure.
As the coalition prepared to mark its first 100 days in office, the Liberal Democrat leader said they had already confounded sceptics who warned his party's pact with the Conservatives would not work.
Writing in a national newspaper, he said that they were already delivering radical policies rather that the "bland, cautious mush" which some critics predicted was all that they could achieve.
"We will govern for the long term and we'll stick to our plan," he declared.
His comments will be seen as a rallying cry to his own party which came under intense pressure over its support for the Conservatives. Many Lib Dem MPs are deeply unhappy with the programme of swingeing spending cuts and steep tax rises which the Government is putting in place to tackle the record deficit.
Mr Clegg acknowledged that they would have to "play the long game", but insisted that it was already paying dividends with measures to restore civil liberties and to create a fairer tax system.
"So far, this coalition Government has confounded expectations. First we were told the coalition agreement wouldn't work. Now we're told it won't last. We intend to confound expectations again," he said.
"One hundred days? That's not the prize. It's the next five years that count."
Mr Clegg insisted the fact the coalition partners had to be "up front" about their difference - in contrast to the "factionalism and back-biting" of the Labour years - meant that it was actually easier to overcome them.
"So we have had a much more radical first 100 days than conventional wisdom predicted, confounding the myth that compromising on policies means you are left with a bland cautious mush, the common denominator approach," he said.
