US Treasury calls on UK and EU to ensure smooth Brexit

US Treasury Secretary Jack Lew speaks during a panel discussion on financial inclusion at the 2016 Annual Meetings of the International Monetary Fund Headquarters and the World Bank Group on October 7, 2016, in Washington, DC. (Photo by AFP)

The United States has called on the United Kingdom and the European Union to ensure their economies remain "highly integrated" after Britain leaves the 28-nation bloc.

US Treasury Secretary Jack Lew made the request after meeting withsenior executives from Barclays, Standard Chartered, the London Stock Exchange, Citigroup, J.P. Morgan and a trade body in London on Monday.

"The secretary reiterated that a transparent, smooth and cooperative process that results in a highly integrated economic relationship is in the best interests of Europe, the United States, and the global economy," a spokeswoman for Lew said.

"Secretary Lew added that the United States remains committed to maintaining its special relationship with the UK and its strong partnership with the EU,” the official added.

Several banks and businesses are concerned that British Prime Minister Theresa May has still not pronounced outlines of Britain’s future trading relationship with the EU as she prepares to start the exit talks formally early next year.

The UK's financial services industry is also worried that it will lose the right to sell products across the EU.

"During the conversation, Secretary Lew underscored the United States is committed to continuing to work with the UK and the EU to ensure sustained economic stability ... as the UK and the EU negotiate their future economic relationship," his spokeswoman said.

Former British Prime Minister Tony Blair has said Britain should keep its “options open” on whether or not to leave the EU until after Brexit talks with the bloc are completed.

During an interview on Friday with BBC radio, Blair described the EU referendum as “a catastrophe,” and said UK voters should be given the option of a second EU referendum.

Economic growth in the UK is expected to slow significantly next year, due to uncertainty over of the Brexit vote.

Experts have warned that leaving the EU will severely hurt London’s position as a financial hub, unless the UK decides to keep its access to the EU's single market by loosening its stance on immigration.

If the UK loses its access to the single market, the resulting increase in the costs of doing business and exporting to the EU would hurt Britain’s competitive position in Europe.