The new home secretary will host talks on how to stop people smuggling in her first major engagement in the role.
Shabana Mahmood will host the so-called Five Eyes security alliance, holding talks between counterparts from the US, Australia, Canada and New Zealand.
The security alliance discussion comes after an estimated 1,000 people arrived by small boat in Britain over the course of a single day, with French authorities saying 24 people were rescued while trying to cross the English Channel.
Ms Mahmood said the numbers, which take the yearly total to more than 30,000 in record time, were “utterly unacceptable” and that she expected migrant returns under a deal agreed last month with France to begin “imminently”.
She was promoted into the role Friday during a dramatic reshuffle of Keir Starmer’s top team, which followed in the wake of Angela Rayner’s resignation over her tax affairs.
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Sir Keir will now be hoping to draw a line under the fallout of his former deputy’s departure, as well as a summer dominated by criticism of his government’s handling of the small boats crisis.
Ms Mahmood said the Five Eyes intelligence sharing pact would “agree new measures to protect our border”. The group will also discuss new measures to tackle child sexual abuse online, as well as the spread of deadly synthetic opioids, the Home Office said.
Ms Mahmood said: “Rebuilding our reputation on the world stage is how we tackle serious organised crime and secure our borders.”
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“The Five Eyes might be drawn from different corners of the globe, but we are united by our alliance,” she added.
“As the security threats we all face become more complex and span continents, we are stronger and safer together.”
She will be joined at the talks by US secretary of homeland security Kristi Noem, Canadian public safety minister Gary Anandasangaree, Australian home affairs minister Tony Burke and New Zealand minister Judith Collins.
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The Prime Minister has told his new ministers to “go up a gear” in delivering on Labour’s agenda, part of which now involves a toughened immigration policy as he faces pressure in the polls from Nigel Farage’s Reform UK.
In Ms Mahmood’s first full day in the job, she met the head of Scotland Yard to receive a briefing on the policing operation in response to protests in London.
“Supporting Palestine and supporting a proscribed terrorist group are not the same thing,” she said.
“An honour to visit Sir Mark (Rowley) and the Metropolitan Police to see them at work policing protests yesterday.”
Almost 900 people were arrested in central London at a protest against the banning of Palestine Action.