OTTAWA — Finance Minister Bill Morneau is warning Britain that tens of thousands of jobs at Canadian firms in the United Kingdom are vulnerable because of the debate around the country's potential exit from the European Union. Speaking to reporters in London, Morneau says Canadian companies with investments in the U.K. are anxious about the uncertainty caused by the so-called Brexit vote later this month. He says Canadian businesses that invested in the U.K. to access the European market may be forced to rethink their strategies. Finance Minister Bill Morneau says British jobs at Canadian companies are at risk over the Brexit vote, as those companies had expected to have access to EU markets. (Canadian Press photo) Morneau says Ottawa believes the U.K. is stronger as part of a united Europe — which he adds is also better for the Canadian economy and the still-to-be-signed Canada-EU free trade deal. He says he hopes Britons will consider this as they make their decision in what is expected to be a close referendum. Last month, Prime Minister Justin Trudeau suggested in an interview with Reuters news agency that it would be difficult for Britain to replicate its own version of the Canada-EU free trade deal, known as CETA. Copies of 'The Sun' newspaper sit on a news stand in London, U.K., on Tuesday, June 14, 2016. The tabloid paper, published by Rupert Murdoch's News Corp., on Tuesday urged readers to vote to leave the E.U. in the U.K.'s referendum next week. (Luke MacGregor/Bloomberg via Getty Images) Morneau said Ottawa estimates CETA will create about a 20 per cent increase in trade and will deliver a 0.77 per cent annual boost to Canada's gross domestic product. "We're watching in Canada and we're anxious," Morneau said Tuesday. "(Canadian businesses) see that the decision they took to invest in the United Kingdom in order to have the opportunity for the European market is now at risk, based on this decision. "So, tens of thousands of employees — people that are employed by Canadian businesses in the United Kingdom — those people are more vulnerable as a result of this discussion."