Top Wall Street banks are planning to move from London to Dublin amid fears Britain will withdraw from the European Union.

Reports in the Irish Independent and Financial Times suggest that leading banks are already making plans to move some of their London-based operations to Ireland.

The reports list Citigroup Inc, Morgan Stanley and Bank of America Corp as among those considering Ireland as an alternative location for some of their European activities if they need to move them out of the UK.

The reports indicate that the plans are at a very early stage.

A spokesman for Morgan Stanley declined to comment on the article while representatives of Bank of America and Citigroup could not be reached for a response.

The moves come as British Prime Minister David Cameron vowed to conduct a referendum on a renegotiated EU membership if the Conservative party is re-elected in 2015.

The debate has raised fears that the world’s sixth-largest economy could quit the union it joined in 1973.

The reports say the situation worries many in the City of London, the financial center that accounts for roughly one-tenth of the British economy.