What’s next and what’s at stake in U.K. election

LONDON—British Prime Minister Theresa May has called a general election for June 8. Here’s a brief look at what happens now, and what’s at stake.

WHY DID MAY MAKE HER MOVE?

May took power in July, after David Cameron resigned following Britain’s vote to leave the European Union. A new ballot offers her the chance to seek her own mandate and to increase the Conservative Party’s narrow majority in the House of Commons, where it holds 330 of 650 seats.

Britain formally triggered the process for leaving the EU last month, but more turmoil is in store as the country negotiates a divorce that will affect every aspect of life in the U.K.

IS IT A DONE DEAL?

British prime ministers used to have the power to call elections at will, but the Fixed-Term Parliaments Act, passed in 2011, makes things more complicated. Under the act, national elections are held every five years, in May. The prime minister can call an early election if two-thirds of lawmakers support it.

May will ask the House of Commons to vote on the snap election on Wednesday. Jeremy Corbyn, leader of the main opposition Labour Party, has said he welcomes an election, meaning the election call will almost certainly pass.

WHAT’S AT STAKE?

Negotiations to leave the EU will be arduous. The talks will deal with money, trade, defense, to name but a few key topics. If May were to gain more seats, she would be able to have more freedom to pursue her own agenda, and to neutralize those inside and outside her own party who disagree with her positions.