Prime Minister Boris Johnson will promise on Wednesday to end the delays over Britain’s departure from the European Union if he wins next month’s election and he will describe the opposition Labour Party’s plans as political “onanism”. Johnson was scheduled to make a campaign speech at a factory in the West Midlands where, according to prepared remarks, he will say that the rest of the world cannot understand why so much time has been spent agonising over Brexit. Britons will vote on Dec. 12 in an election called to end three years of deep disagreement over Brexit that has sapped investors’ faith in the stability of the world’s fifth largest economy and damaged Britain’s standing in the world.