Newly-appointed shadow chancellor John McDonnell has warned David Cameron will not be given a "free hand" over the European referendum - but said Labour would wait to discover what renegotiations had been made before deciding which option to support.
He also confirmed new leader Jeremy Corbyn did want to remain in the EU.
Speaking outside his home this morning, the left-wing politician - a long-time ally of Mr Corbyn - said their main aim was to develop a "good Europe."
We want to see what Cameron's package of negotiations are, and then we'll take a decision on whether or not we need to negotiate our own package. We're consulting others about the sort of reforms that we want.
Jeremy said quite clearly that he wants to remain in Europe, but he wants to see what Cameron's package is. The British people want to know that as well.
We're not going to give Cameron a free hand on any negotiations at all. We want to see what he comes up with. At the moment it's trying to get a good Europe, a Europe that serves all our interests.
I think we can do that.
He also denied reports that the atmosphere at last night's party meeting had been frosty, saying he thought it had been "warm", adding: "I've been in a lot worse meetings, I tell you."
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