Boris Johnson has been accused of lying to the public over his promises to reduce immigration.
The Conservative Party has set out its plans for an Australian-style points-based immigration system, which would put no limits on highly educated and award-winning workers, investors or entrepreneurs coming to Britain after Brexit.
It would also fast-track and offer reduced fees to doctors, nurses or social care workers who want to come to work in the NHS.
The Prime Minister, in an interview with Sky News's Sophy Ridge On Sunday programme, said he could guarantee "numbers will come down" as part of the "controlled" measures.
But shadow health secretary Jonathan Ashworth said Mr Johnson was "misleading" voters about the effectiveness of the proposed new system.
He also argued the Tories would have "no democratic control" over the immigration numbers due to plans to set-up an independent committee to oversee the points-system implementation.
Labour's Mr Ashworth told Sky News: "He said the committee will be independent in the same way as the Bank of England is independent so he is misleading people when he says he is bringing immigration down because there will be no democratic control.
"There will be no accountability over any decision that any immigration minister makes because it will be handed over to a statutory independent committee - so again Boris Johnson is lying to the British people."
Mr Ashworth said the UK "should absolutely maintain free movement for the National Health Service and the social care sector" as they "literally could not survive if we did not continue to recruit internationally".
Brexit Party leader Nigel Farage, also appearing on the Sophy Ridge programme, accused the PM of having "always been very soft" on immigration.
Despite wanting to cut numbers coming in from abroad, Mr Johnson has suggested there could still be a domestic population boom if the electorate put him back into Downing Street and allow him to push through his Brexit deal.
He told the Sunday Times: "Cupid's darts will fly once we get Brexit done. Romance will bloom across the whole nation.
"There was one after the Olympics, as I correctly prophesied in a speech in 2012. It was quite amazing. There was a big baby boom."
The paper notes that, while 2012 did see the biggest baby boom for 40 years, the cause was said to be the release of the erotic novel Fifty Shades Of Grey rather than the Olympics.
During his appearance on Sky News, Mr Johnson declined to answer three times when asked whether he would resign if he loses the election.
Also asked about her own future, Liberal Democrats leader Jo Swinson said she would be going nowhere, even if her pro-European Union party ended up with fewer MPs than in the snap poll two years' ago.
Ms Swinson told Ridge: "No, I was elected as leader of the Liberal Democrats four months ago, that's a big job to be done and four months in I've made a start."
Labour's John McDonnell admitted, should his party lose the election, that the anti-Semitism allegations which have dogged Labour might play a part in the result.
The Sunday Times reported that a leaked recording from Labour's disciplinary committee in October indicated that 130 cases remained outstanding even though the "vast majority" were reported to officials 18 months ago.
Questioned on the BBC's Andrew Marr programme about the role anti-Semitism could play on Labour's election chances, the shadow chancellor said: "I worry that this has had its effect, and we've done everything I think we can possibly do.
"We've apologised to the Jewish community."
Tory chairman James Cleverly also apologised for Islamophobia in his own party and vowed to "investigate" claims.
"Of course I'm sorry," he told BBC 5Live's Pienaar's Politics. "And I'm sorry when, you know, people do or say things that are wrong."
He said an investigation to "specifically look into Islamophobia in my party" would be "initiated this calendar year".