Sir Keir Starmer has pledged to slash levels of migration to the UK, while Rishi Sunak has promised more community care services in his first major health offer of the election campaign.

The Labour leader is putting the migration plan in his manifesto, and it will include passing laws to ban law-breaking employers from hiring foreign workers and to train more Britons.

Last year’s net migration figure of 685,000 has “got to come down,” he told The Sun on Sunday, as he vowed to “control our borders and make sure British businesses are helped to hire Brits first”.

While encroaching on traditional Tory territory, Sir Keir hit out at successive Conservative governments for promising but failing to cut numbers.

A Labour government would bar bosses who break employment law – for example by failing to pay workers the minimum wage – from hiring foreigners, the newspaper reported.

It would also legislate to link the immigration system to training, with businesses applying for foreign worker visas having to train Britons to do the jobs.

Sir Keir declined to name the target level for migrant numbers, or a timeline.

He will be seeking to shift the focus away from the Diane Abbott row that has dogged his campaign, but the tough talk on migration could risk inflaming tensions with the Labour left.

A report in The Sunday Times that a number of left-wingers including Ms Abbott have been offered peerages in return for quitting could also reignite the infighting.

They have been told they would be elevated to the Lords if they made way for allies of the leadership team in their seats, according to the newspaper.

Despite the debacle over Ms Abbott’s candidacy, Labour saw its lead over the Tories widen to 20 points in an Opinium poll. It showed Sir Keir’s party on 45% – up four points since last weekend – while the Conservatives were down two percentage points on 25%.

It is a blow to the Prime Minister, who is seeking to fire up his campaign with a promise to boost community care.

A hundred new GP surgeries and 50 community diagnostic centres would be built were he to remain in No 10, funded by slashing the number of NHS managers, the Tories said.

They pledged to expand their Pharmacy First scheme, which allows patients to access some treatments via their pharmacy without having seen a GP first.

Mr Sunak said the proposals would make it “quicker, easier and more convenient for patients to receive the care they need and help to relieve pressure on hospital services”.

But shadow health secretary Wes Streeting said the Conservatives have cut 1,700 GPs since 2016, adding: “Patients are finding it harder than ever before to see a GP, so why would they trust this latest empty promise?”

The Liberal Democrats have also attacked the Tories’ record on health.

Sir Ed Davey’s party promised to reverse £1 billion in Conservative cuts to the Public Health Grant, which provides local authorities with funding for public health projects.

The Lib Dems said they would fund the investment into local services through a crackdown on tax evasion.

Labour also restated its promise to turn the Tories’ “botched” apprenticeships levy with a new growth and skills levy, allowing firms to use up to 50% of their levy contributions to fund training through routes other than apprenticeships.

Rishi Sunak and the Tories' battle bus
Prime Minister Rishi Sunak at the launch of the Conservative campaign bus at Redcar Racecourse (Jonathan Brady/PA)

Shadow education secretary Bridget Phillipson said: “Businesses are crying out for help to tackle skills shortages, so Labour will give them the flexibility needed to create skills training opportunities and drive economic growth.”

But Education Secretary Gillian Keegan claimed the “ill-thought-through policy will halve the number of apprenticeships, slash the budget by £1.5 billion, and disadvantage small and medium-sized businesses”.

Sir Keir and Mr Sunak appear to be taking a day off from touring the country on Sunday after a busy week of campaigning culminating in the launch of their parties’ battle buses on Saturday.

Health Secretary Victoria Atkins will promote the Tory health plan on the Sunday morning broadcast round, with shadow home secretary Yvette Cooper appearing for Labour.

North of the border, First Minister John Swinney will urge people to “vote SNP to put Scotland’s interests first” as he formally launches the party’s General Election campaign in Glasgow.