The coalition government was united over a decision to block changes to the European Union treaty, Foreign Secretary William Hague said on Friday.
The move threatens to drive a wedge between the Conservatives and their smaller pro-Europe Liberal Democrat coalition partners.
The policy that we're implementing here is the agreed policy of the coalition government, Hague told BBC Radio 4, adding that Liberal Democrat leader Nick Clegg, the deputy prime minister, had been consulted during the course of overnight EU talks in Brussels.
Everybody signed up to it in advance. We would either get the safeguards that we required and make a Treaty of the 27 EU members or if we didn't we would refuse to agree to it, added Hague, speaking from Brussels.
(Reporting by Keith Weir)