LONDON: Britain's Trades Union Congress will support a second referendum on a Brexit deal if Prime Minister Theresa May fails to get a deal with the European Union that can help the country's workforce, General Secretary Frances O'Grady said on Sunday.

O'Grady, who leads the body which groups 48 trade unions, told the BBC's Andrew Marr show: "We should extend Article 50 (which gives two years to negotiate an exit deal). We should focus on getting a deal that is actually good for this country and that means good for working people.

"But if the prime minister is not prepared to do that then I think it has to go back to the people and if there isn't going to be an early general election the only way is a popular vote."