Britain’s most senior Jewish religious leader stepped into Britain’s election campaign Monday, saying the country’s main opposition leader has allowed the “poison” of anti-Semitism to take root in his party.

Chief Rabbi Ephraim Mirvis, spiritual leader of the U.K.’s Orthodox Jews, said that “the very soul of our nation is at stake” in the Dec. 12 election. Writing in The Times of London newspaper, Mirvis said Labour Party leader Jeremy Corbyn and his allies had failed to stop anti-Jewish prejudice and “hounded” those who tried to challenge it.

Labour’s election campaign has been dogged by recurring allegations that Corbyn – a longtime champion of the Palestinians – has allowed anti-Jewish prejudice to fester in the left-of-center party.

Corbyn has called anti-Semitism “a poison and an evil in our society” and says he is working to root it out of the party.

But, Mirvis said, “the way in which the leadership has dealt with anti-Jewish racism is incompatible with the British values of which we are so proud.”

“It is not my place to tell any person how they should vote. … I simply pose the question: What will the result of this election say about the moral compass of our country?” he wrote.

It is rare for a religious leader to publicly call out the leader of a British political party.

The governing Conservatives, meanwhile, are defending an election platform that is light on policy proposals, as they try to avoid squandering the party’s poll lead before the nation votes in less than three weeks.

Prime Minister Boris Johnson’s party is campaigning heavily on a promise to “get Brexit done” by taking Britain out of the European Union on the currently scheduled date of Jan. 31, if it wins the election next month. The phrase “get Brexit done” appears 22 times in the party’s 59-page election manifesto.

“When we get Brexit done, believe me we will unleash a tide of investment into this country,” Johnson told supporters as he campaigned Monday in north Wales.

Despite the bravado, Culture Secretary Nicky Morgan conceded that leaving the bloc would only be “the first big step” to completing Brexit, because it would be followed by negotiations on a new trade relationship with the bloc.

All 650 seats in the House of Commons are up for grabs in the election, which is taking place more than two years early. Johnson sought the early vote in hopes of winning a majority and breaking Britain’s political impasse over Brexit.

The Conservatives lead Labour in opinion polls, and the governing party is taking a cautious approach in the remaining 17 days of the campaign.

On Sunday, the Conservatives published an election manifesto — the bedrock of British parties’ election campaigns — that is light on plans for the country beyond Brexit.

It includes voter-friendly promises to fill potholes and scrap some hospital parking charges, and commits to a modest increase in public spending, though far less than that proposed by Labour.

Labour has set out plans for a radical expansion of public spending and state ownership if it wins the election.

The Conservatives also promised to increase the number of nurses working in the state-funded health service by 50,000 within six years — though part of that increase is set to be achieved by reducing attrition rather than training and hiring new medics.

Notably, the Conservative manifesto does not include a proposal for how to fund the increasing cost of social care for the elderly and others who need it, despite Johnson’s earlier promises that the Conservatives would grapple with the difficult issue.

Many Conservatives believe a botched social-care proposal in the party’s 2017 election platform — dubbed a “dementia tax” by opponents — cost the party its majority in Parliament and led to more than two years of political deadlock over the terms of the country’s deparure from the EU.

Paul Johnson of economic think tank the Institute for Fiscal Studies said the Conservative promises would be considered modest if they were put forward in an annual budget.

“As a blueprint for five years in government, the lack of significant policy action is remarkable,” he said.

Britain’s political parties are under scrutiny for their use of social media, one of the key election battlegrounds. The Conservatives have been especially criticized for rebranding their press office Twitter account “factcheckUK” during a televised debate.

Tim Berners-Lee, inventor of the World Wide Web, called the deceit “brazen.”

Berners-Lee, who has warned against the spread of online misinformation, also said it would be better if there were “no targeted political advertising during the election season” in Britain and the U.S.

Johnson has said that if he wins the election he will begin the process of getting his Brexit deal through Parliament before Christmas, so that British families could “enjoy their festive-season free from the seemingly unending Brexit box-set drama.”

Lawmakers approved the deal in principle last month, but Johnson withdrew it after they asked for more time to scrutinize it.

The government said Monday that lawmakers will return to Parliament on Dec. 17. If Johnson is reelected, the government will introduce its legislative agenda two days later in a speech delivered by Queen Elizabeth II.

If Labour wins or there is an uncertain outcome, the queen’s speech is unlikely to be held until January, when Britain will — once again — be facing a looming Brexit deadline.

The U.K. is due to leave the bloc on Jan. 31, after failing to meet two previous departure dates amid wrangling in Parliament.

(AP)