London has regained its crown as the world's leading financial centre, according to a survey of industry professionals.

The city benefited from the clear election victory by the Conservatives to overtake New York. 

The online survey of more than 2,000 individuals ranked 84 cities around the world in terms of the business environment, infrastructure, quality of workforce and financial sector development. 

London, which had top billing for seven years in a row in the twice-yearly survey, lost the top spot to New York last year. 

The shock election triumph by the Conservative party in the UK election in May helped it overtake New York this time, research company Z/Yen, which published the survey, said.  

Ahead of the vote most polls had predicted a hung parliament, and a phase of political and economic instability.

The result comes despite Europe's biggest bank HSBC and its Asia-focused rival Standard Chartered currently deciding whether to axe their London headquarters because of a government levy on bank profits and the uncertain outcome of an upcoming vote on Britain's membership of the European Union.

London came top in every category, the report showed. 

HongKong, Singapore and Tokyo took third, fourth and fifth places respectively. Toronto, San Francisco and Washington DC were also named in the top 10. 

The only other European city to rank among the world's 10 leading financial centres was Zurich while Frankfurt was the European Union's second highest ranking city in 14th place. 

Z/Yen's Mark Yeandle said that London'sfuture status as the world's top financial centre was also threatened by government efforts to control immigration. 

"You can't have an international financial centre without an international workforce," he stated.