The City of London has raised concerns over David Cameron’s strategy in Europe, warning that the British prime minister’s wishlist of “safeguards” in December could have damaged its standing as Europe’s financial centre.

The differences over Britain’s diplomatic priorities, first aired earlier this year, have taken on renewed significance days before a key EU summit as Mr Cameron prepares a fresh list of demands for legal protections if a European “banking union” is formed.

Britain rejected a new EU fiscal treaty in December after Mr Cameron failed to win safeguards for the EU single market for financial services – demands France derided as an unacceptable “opt-out” for the City. But senior representatives of Britain’s financial centre later told Treasury ministers that most of the “protocol” on financial services was misguided or unnecessary and liable to backfire, according to an internal City of London Corporation analysis of the wishlist seen by the Financial Times.