Chancellor George Osborne has raised the prospect that Britain could leave the European Union unless there is change in Brussels.
In an interview with the German Die Welt newspaper, the Chancellor said that he very much wanted the UK to continue as an EU member state.
However he made clear that in order for that to happen, there would have to be meaningful reform of the current arrangements.
"I very much hope that Britain remains a member of the EU. But in order that we can remain in the European Union, the EU must change," he said.
A Treasury aide insisted that his comments were fully consistent with the Government's position - that the EU needs to change "and indeed is changing".