Commons Leader and prominent Brexit supporter Andrea Leadsom resigned from Theresa May's Cabinet on Wednesday, saying she no longer believes that May's approach would deliver on Brexit.

"No one has wanted you to succeed more than I have," wrote Leadsom, who was May's head-to-head rival for the prime ministership in July 2016, before withdrawing from the contest. "I do now urge you to make the right decisions in the interests of the country, this government and our party," she added.

The resignation came a day before the UK voted in elections for the European Parliament, as May faced a fierce backlash against her latest maneuver to get the government's Brexit withdrawal deal passed.

Theresa May has so far resisted mounting calls for her own resignation, despite growing opposition from lawmakers and Conservative ministers to her latest Brexit plan.

Read more: UK's 'Mr. Brexit' Nigel Farage eyes EU election success

The latest iteration of May's deal included offering lawmakers a vote on whether to hold a second Brexit referendum — once her legislation passes the first stage — and closer trading agreements with the EU in the future.

Several lawmakers who had backed May in her previous Brexit votes drew a line in the sand, saying they could not support her new plan.

"I have always maintained that a second referendum would be dangerously divisive, and I do not support the government willingly facilitating such a concession," Leadsom wrote in her letter of resignation.

Read more: Brexit: UK Labour Party breaks off talks with Theresa May

"I do not believe that we will be a truly sovereign United Kingdom through the deal that is now proposed," Leadsom continued. She also claimed that "recent Brexit-related legislative proposals have not been properly scrutinized or approved by cabinet members."

A spokesperson for Downing Street has said Leadsom has served with distinction and great ability, and that the prime minister is grateful for all her work.

Ian Lavery, the chair of the opposition party and Labour lawmaker, said Leadsom's resignation underlined that "the prime minister's authority is shot and her time is up."

Leadsom withdrew from a 2016 leadership contest  — in which she and May were the last two contenders — following contentious comments about her rival having no children.

mc/rc (Reuters, AP) 

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