House of Commons leader Andrea Leadsom resigned on Wednesday, the 36th minister to resign under May’s watch.

But May’s agreement was also brushed off by the opposition Labour Party, with leader Jeremy Corbyn dismissing it as a “rehash” of what has been previously discussed. Talks between Labour and Conservative Party lawmakers to break the Brexit impasse had broken down last week.

May had survived a vote of no-confidence by her own backbenchers in December, leaving her secure until December this year. However, British media reported that the 1922 Committee of backbench MPs were threatening to change the rules if she did not step down after Thursday’s elections.

May’s formal announcement of her plans to depart will add fuel to a leadership race already underway. Tom Tugendhat MP told Sky News Wednesday that “the shadow boxing campaign that is the leadership campaign already began a few weeks ago.”

Former Foreign Secretary Boris Johnson, who resigned over May’s handling of Brexit, said last week that he intended to enter the leadership race whenever a vacancy arose. Other candidates could include Home Secretary Sajid Javid, former Brexit Secretary Dominic Raab and Andrea Leadsom — who was a candidate in the 2016 leadership race.

Her announcement could complicate the upcoming June 3 state visit by President Trump to London to mark the 75th anniversary of D-Day, where he will also meet with Queen Elizabeth II.

May will still be in office during that visit, meaning it will nix the chance for a new prime minister to forge ties with the American president at a time where such relations are vital. A U.S.-U.K. trade deal is a top priority for the U.K. as it looks to depart from the European Union and begin making its own trade agreements — and Trump has said “the potential is unlimited” for such a deal.