The argument about when the general election will be held appears tonight to be over following a blunder by Chris Bryant.

Speaking to diplomats at Canning House, a diplomatic think-tank, the Europe Minister seemed to confirm the widely held belief that the poll will be held on May 6 – the same day as the local council elections.

Referring to recent tensions between Britain and countries in South America, Mr Bryant said: “I hope that by the time of the general election on May 6, relations will have improved.”

His loose lips will anger the Prime Minister and senior party strategists, as it’s common knowledge that ministers have been told not to talk in detail about when the election will be called, in order to keep the Conservatives in the dark and so not to help them plan for the big day.

Mr Bryant has a history when it comes to untimely disclosures. In October, he used Twitter to tell his 378 followers, and more importantly journalists, that he was “off to work with a new job.” This forced Downing Street to confirm that he had indeed been promoted from minister for foreign affairs to to the Europe job at the Foreign Office.

Earlier this month he also delivered an angry attack at the Eurostar service after being caught up in delays on the micro-blogging service.

Traveling back to the UK after two days of talks in Paris he posted: “I am rapidly developing a very severe hatred of Eurostar as we are travelling at about a mile a year.”