Cameron, Merkel in show of unity

"Where there is a will there is a way," Merkel said at a joint news conference with Cameron in Berlin, stressing that she would work constructively with the UK government about their "wishes and expectations." She made it clear that Germany wants Britain to stay in the bloc.

Cameron, who is visiting several EU partners to drum up support for reform in the EU, also said that "it is right for the UK to stay in a reformed union." Cameron is aiming for a looser union, saying that "Europe needs to have flexibility of a network not the rigidity of a bloc." He has promised voters an in-out referendum on EU membership before the end of 2017, which has led to an ongoing debate about a possible "Brexit," namely a British exit from the EU.

Merkel said discussions had begun over content and whether a treaty change would be necessary - something she said "you cannot completely rule out." She said some of Cameron's suggestions could "possibly" be in Germany's interest - like what she called the "abuse of the benefits system in the EU" that are a side effect of the bloc's open borders.

Reforms ahead of referendum?

Both leaders dodged questions about whether changes to the EU treaty were achievable before Britain holds a referendum on its membership in the EU, with Cameron saying that it was "about starting a process" and that the "substance" of reforms was the most important factor.

Cameron has already held talks with Polish, Dutch and French leaders on his EU reform plans.

FIFA scandal

Cameron and Merkel also answered reporters' questions about the scandals at FIFA and the ongoing FIFA Congress in Zurich. Asked whether FIFA President Sepp Blatter should be re-elected this weekend, Cameron said "we've seen the ugly side of the beautiful game" and that "he should go and the sooner that happens, the better."

Merkel stressed that FIFA needed to prioritize the fight against corruption, "whoever gets elected."

ng/msh (AP, Reuters, dpa)