The U.K.’s opposition Labour Party effectively extinguished all prospect of a second referendum on Britain’s membership in the European Union, acknowledging that Brexit was a fait accompli that meant immigration rules must change. Keir Starmer, the party’s Brexit spokesman, used a speech on Tuesday to offer an alternative vision to Prime Minister Theresa May’s Brexit strategy, offering to soften the blow by immediately guaranteeing the rights of EU citizens to stay in the country if Labour wins the June 8 snap election. The upshot was that the main opposition “genuinely accept the outcome of the referendum.” But Starmer offered to fight to keep the benefits of the single market and customs union—two things May has indicated she’s prepared to give up—and envisaged a process whereby there would be a three to four years of transition after the obligatory two years of negotiations. “We recognize that immigration rules will have to change as we exit the EU, but we do not believe that immigration should be the overarching priority,” Starmer said. “We believe in building a new relationship with the EU – not as members but as partners.” He accused May of having a “rigid” and “reckless” approach to Brexit talks. Labour is trailing in opinion polls that suggest it will lose seats in the election, strengthening May’s hand in Brexit talks and reducing opposition from lawmakers in the House of Commons to her strategy.