Merkel willing to compromise to keep UK in EU
German Chancellor Angela Merkel has said that the EU is likely to negotiate a treaty change if that is what's necessary to retain the UK.
"I'm optimistic that if we all want it, we'll find a good solution," she told the BBC, adding that she was not losing sleep over Cameron's demands.
There is speculation that the EU could present the UK with a special treaty protocol to accommodate concerns, in line with those that made Danish and Irish opt-outs legally binding.
However, treaty change remains controversial, with France among the countries wary of it. The Lisbon Treat negotiation, signed in 209, was eight years in the making and required to Irish referendums.
However, Merkel remains positive: "The EU is a union of 28 member states that have to find compromises. Only when everyone is agreed and happy can we get proper results. That will is there. We have already found many, many solutions for many, many difficult questions - it should be like that in this case too."
Prime Minister David Cameron toured Europe in an effort to gather support for his proposed changes last week, efforts which are likely continue in the run up to the EU referendum, due before 2017.