Britain's new Prime Minister Rishi Sunak on Monday vowed action to come on cross-Channel migrants after his first face-to-face meeting with French President Emmanuel Macron.

The two leaders met on the sidelines of the UN's COP27 climate summit in Egypt, with Sunak under pressure from days of bad headlines on the fate of migrants detained in a UK detention center.

Sunak told UK media that "it was great to meet President Macron to talk about not just tackling illegal migration but the range of other areas in which we want to cooperate closely with the French on." 

"And I think there is an opportunity for us to work closely, not just with the French but with other (European) countries as well," he said.

The British PM added, "You will hear more details about that in the coming weeks as those conversations happen amongst all our teams."

"But I'm actually leaving this with renewed confidence and optimism that working together with our European partners, we can make a difference, grip this challenge of illegal migration and stop people coming illegally," he explained.

Some 40,000 people have crossed the Channel in small boats so far this year, with prediction numbers possibly hitting 50,000 or even 60,000 by the year-end. That has caused a rise in asylum claims and increased accommodation costs estimated by the UK government at £6.8 million ($7.8 million) a day.

Sunak insisted that his Interior Minister, Suella Braverman, was getting to grips with the crisis while stressing it lacked "one simple solution that's going to solve it overnight."

The migrant crisis has been a major cause for concern in the United Kingdom, which vowed to implement tighter border control after it left the European Union.

It also gave rise to tensions between London and Paris, with the former accusing France of not doing enough to cut the flow of migrants.

As the UK supposedly welcomes Ukrainian refugees with open arms, it has different plans for other immigrants, as the Home Office plans to reopen two immigration centers enough to house 1,000 asylum seekers.

Currently, the UK government runs seven immigration detention facilities, as well as a few short-term holding facilities throughout the nation, which can house 3,000 people at once.

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