LONDON (Reuters) -Nearly 20,000 asylum seekers have arrived in Britain on small boats so far in 2025, a record high for the first six months of the year, adding pressure on Prime Minister Keir Starmer as the government works to reduce the numbers.

Data from Britain's interior ministry showed that 879 migrants arrived on Monday, taking the total for the first half of 2025 to 19,982, a 50% jump from a year earlier.

Starmer is under pressure to deal with the thousands of people who cross the Channel each year on dangerous, inflatable dinghies, a key issue for voters as he pledges to "smash the gangs" behind the people smuggling trade.

The government says more than 24,000 people with no right to be in the UK had been returned since it took office last July, and that good weather and new techniques to pack more people into boats were helping more migrants make the crossing. In 2024, 73 people died trying to cross the Channel in small boats.

The government also pledged to end the costly use of hotels to house asylum seekers.

But Labour's failure to get a grip on small boat arrivals has helped boost Nigel Farage's right-wing, anti-immigration Reform UK party, which has topped national opinion polls.

"(The small boat numbers are) a record and will only increase if we continue to give them everything when they arrive," Farage wrote on X.

Starmer had set out proposals in May to bring down overall immigration, warning that Britain risked becoming "an island of strangers", remarks that were criticised as being too divisive and for which he has since expressed regret.

Earlier this year, the government also upheld a ban on asylum seekers being able to claim protections under modern slavery and other human rights laws, a move criticised by human rights groups.

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(Reporting by Catarina Demony; Editing by Sachin Ravikumar)