SIR Keir Starmer has refused to say his plan to invite tens of thousands of Europeans back to the UK will be capped.

Despite talking tough on reducing legal migration, the PM is negotiating a visa programme to allow EU citizens under 35 to work or study in the UK.

When asked by the Sun about his talks with Brussels regarding a proposed Youth Mobility Scheme, Sir Keir avoided confirming if there would be a limit on the number of new visas issued.

Similar schemes with other countries last up to four years meaning someone who applied at 35 could live and work in the UK until they were 39.

Before meeting with the EU in London on Monday to discuss a “reset” with Brussels, the Prime Minister emphasized that the agreement would be “beneficial for our economy” even with already high net migration numbers.

Moreover, he did not rule out the possibility of the UK aligning with EU rules on goods to minimize the inspections on food entering the EU market.

The PM refused to rule out “Dynamic Alignment” on rules which would see the  UK mirror Brussels laws without any input to set them.

The PM told the Sun he would not give a running commentary on talks but insisted he would not break his manifesto commitment to bring back Free Movement entirely.

Yet he repeatedly refused to say whether accepting Brussels demands for a mobility scheme would have an upper limit on numbers despite pressure from the Home Office to set a cap.

He later said: “We have to respect the outcome of the referendum and that’s the framework in which we have been negotiating.”

Separately last night Government insiders insisted French trawlers will not be allowed to catch “a single fish more” in British waters than its current quota under Sir Keir Starmer’s latest offer to the EU.

As talks with Brussels go down to the wire ahead Monday’s summit, government sources told The Sun the deal on the table will not dilute UK fishermen’s stocks.

But they warn it will not be better than the post-Brexit deal struck by Boris Johnson – likely to spark anger from fishermen already angry with European nets off our shores.

Under the 2020 deal, EU vessels would reduce their catch gradually by 25 per cent until 2026 when the agreement is up for review.

A Government insider said: “The French especially are making fresh demands on our fish but so far we’re not budging. It won’t be better than the deal we’ve currently got, but we’re trying our damndest to make sure they don’t have a single fish more.”

Last night the PM told reporters: “When we started this process the President of the Commission, Ursula von der Leyen and I agreed we wouldn’t do megaphone diplomacy.

“We wouldn’t go running to the nearest microphone to make our respective arguments and criticisms. Because of that we’ve made good progress and I’m confident we will make really good progress into Monday.”