The Labour leader is set to name people smuggling, terrorism, climate change and weakening democracy as the four major threats facing Western countries.

He is also set to declare protecting the UK's borders an "acute security concern".

Sir Keir is at a summit in Montreal for "progressive" politicians - including Canadian leader Justin Trudeau, Norway's premier Gahr Store and former prime minister of New Zealand Jacinda Ardern.

The Labour leader is also due to face questioning on Sky News' Trevor Phillips on Sunday.

Speaking ahead of the summit, Sir Keir said: "One of the most acute security concerns in the UK right now is border security, because the government has lost control of the borders.

"That basic rule that it ought to be the UK government who decides who comes to our shores has been conceded by the government to criminal gangs, who are putting people in boats to go across the Channel.

"So that is the particular challenge that we face and that is why I'm setting out how we will work with international partners to smash these gangs, restore order to our borders and take a pragmatic approach - get rid of the gimmicks and the rhetoric and actually come up with a solution."

Sir Keir is joined by shadow foreign secretary David Lammy at the summit, the latest in a series of engagements he is taking on the global stage

It also comes ahead of an expected visit to Paris next week to meet French President Emmanuel Macron.

The flurry of engagements has been seen as a bid to appear statesmanlike and burnish his leadership credentials ahead of a likely general election next year.

However, Downing Street has appeared to downplay the significance of the expected Paris trip, describing it as "not unusual".

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It comes after Labour confirmed it could accept a quota of migrants from the EU under a returns agreement it hopes to strike with the bloc if it wins power.

Shadow Cabinet Office minister Nick Thomas-Symonds said the objective was to secure a returns agreement to establish "management and control of the system" as he accused the Conservatives of having "lost control of our borders".

Mr Thomas-Symonds spoke to Sky News while Sir Keir and shadow home secretary Yvette Cooper met European officials in The Hague - and as the party unveiled proposals to treat smuggling gangs "on a par" with terrorists.

However, the potential for a returns agreement attracted controversy, with Tory Party chair Greg Hands accusing Labour of a "shocking open-door policy on immigration".

The EU is currently working on a new returns agreement that would mean each member state takes a minimum annual quota of 30,000 migrants, or pay €20,000 (£17,200) for each person they do not accept.

As well as attacks from the right, Labour faced criticism from Matt Wrack, the president of the Trades Union Congress, who told The Guardian Sir Keir was in "danger of pandering to right-wing Tory rhetoric" on immigration.