Britain's Chief Secretary to the Treasury Liz Truss speaks at the the British Chamber of Commerce annual conference in London, Britain, March 28, 2019. REUTERS/Peter Nicholls

LONDON (Reuters) - British Prime Minister Theresa May’s Brexit deal remains the best option for leaving the European Union despite it having been voted down three times by lawmakers, Treasury minister Liz Truss said on Monday.

The most recent defeat for May’s deal in parliament on Friday “was less than we lost by last time and we are seeing people coming on board with that,” Truss told BBC radio.

“I think we need to carry on looking at how we get the support for that deal,” she said.

Truss said “The answer lies in modifications to the prime minister’s deal to be able to get that to have support.”

She said it was not clear that alternative Brexit plans, such as a customs union, would command the support of a majority in parliament.

Lawmakers are due to vote on Monday on alternatives, several of which call for Britain to have closer ties to the EU than foreseen under the prime minister’s plan.