British Prime Minister David Cameron said today that EU plans to impose a cap on bankers' bonuses put his country's national interests at stake.

He said he wanted to ensure that banks based in Britain did not have their competitiveness eroded.

"There is an important issue here, there are some important British national interests. We are responsible for 40% of the EU's financial services ... We want to make sure that international banks go on being headquartered here in the UK," he told parliament.

Cameron's comments followed a meeting in Brussels on Tuesday at which Britain was left isolated after it failed to secure backing to water down new EU rules limiting bankers' bonuses, a measure that could threaten London's dominance as a financial centre.