Nick Clegg accused Defence Secretary Philip Hammond of "jumping the gun" on Trident, as coalition tensions grow over the future generation of British nuclear-armed submarines.
The Deputy Prime Minister dismissed suggestions that an additional £350 million of funding announced for designing a replacement deterrent "made clear" the Government's commitment to maintaining the system.
Mr Clegg insisted the coalition agreement will not be "undermined or contradicted" and the Liberal Democrats' review into alternatives will continue.
Having seen the papers this morning, I think some people are jumping the gun on this Trident decision.
The coalition agreement is crystal clear - it will not be changed, it will not be undermined, it will not be contradicted.
The final decision on Trident replacement will not be taken until 2016, however much other people may not like it that way.
More top news
Marking Human Rights Day, the opposition leader says a Labour government would fight misogyny and bridge the gender pay gap.
Many council tax bills could be increased by almost 4% but councils warn that this still won't be enough to avoid cuts to services.
The Foreign Secretary raises the plight of the Yemen people in a speech to Gulf leaders days after his Saudi Arabia 'proxy wars' comment.