LONDON (AP) – The deputy leader of Britain’s main opposition Labour Party has described an attempt to oust him as “a straight sectarian attack on a broad-church party.”

Tom Watson, who has been critical of Jeremy Corbyn’s leadership of Labour, told BBC radio that he believes his position on Brexit is behind the move to abolish his post.

On Friday, Jon Lansman, the founder of the pro-Corbyn grassroots Momentum group, proposed a motion to be discussed at Labour’s annual party conference for Watson’s job to be scrapped.

Though that was ruled out of order, it’s set to be discussed again Saturday.

Watson is a prominent supporter of a second Brexit referendum and is urging Labour to campaign for Britain to remain in the European Union in any further vote.