The U.K. Independence Party, which played a key role in Britain's decision to leave the European Union, is in disarray as its leader resists growing calls to quit.

The party's executive backed no-confidence motion in leader Henry Bolton on Sunday, but he is refusing to step down.

Several members of the UKIP leadership quit Monday in protest, including deputy leader Margot Parker and the party's immigration, trade and education spokesmen.

Under former leader Nigel Farage, UKIP was a major force behind Brexit. But it has struggled to maintain its prominence, and Bolton is its fourth leader since the June 2016 EU referendum.

Bolton has faced calls to resign since a newspaper published racist text messages sent by his girlfriend, model Jo Marney. He says he has ended the romantic relationship.