Prime Minister David Cameron said a eurozone banking union should not discriminate against those countries who do not use the single currency.
He told reporters at the EU summit in Brussels that changes within the eurozone affect Britain as they "affect the organisation that we are are part of".
Mr Cameron also reiterated that Britain will not become a eurozone member, adding, "Certainly not while I'm Prime Minister anyway".
More top news
Rain across central Britain with longer, intense downpours with thunder in places this evening. A lucky few will stay sunny and dry.
Planning on going to the London Marathon tomorrow? Read our handy guide first!
Labour plans to cap above-inflation rent rises over a three-year period, if they win the General Election.