Prime Minister Boris Johnson’s bill, backed by a huge parliamentary majority, will take the country out of the 28-member bloc on Jan. 31, and lays the groundwork for sweeping foreign and trade policy shifts.

The 358 to 234 vote marks a significant breakthrough for Johnson, who stormed to electoral victory last week on a pledge to “get Brexit done.” The former mayor of London won the largest Conservative majority since Margaret Thatcher in 1987, confirming his position as prime minister after he took over from Theresa May in July.

Johnson’s majority of 80 seats in the House of Commons meant he was able to pass the Withdrawal Agreement Bill — legislation that will implement the divorce deal hammered out with the European Union. Britain joined the European Economic Community —a precursor to the European Union — in 1973.