A migrant pregnant woman his helped by a man and a child after disembarking from a Royal National Lifeboat Institution lifeboat in London on Wednesday. Reuters

At least 100 people arrived at the port of Dover after being picked up by UK Border Force patrol vessels when entering British waters, an AFP photographer witnessed.

Dozens more, again including young children, were also brought ashore on lifeboats at Dungeness, a headland some 40 Kilometres to the west, after setting out to cross the Channel in small boats, the same photographer reported.

The arrivals came after six Afghan men died and dozens more had to be rescued when an inflatable vessel sank in the Channel in the early hours of Saturday after leaving northern France.

A rescuer carries a child as people, who are believed to be migrants, arrive on a lifeboat, in Dungeness, Britain. Reuters 

Both Britain and France have blamed criminal gangs facilitating the crossings but have attracted criticism themselves from rights groups over their policies towards the issue.

The UK government in particular has been condemned after recently barring arrivals from claiming asylum and pursuing plans to deport them immediately to Rwanda.

Both plans are on hold pending a court challenge to sending the migrants to east Africa.

They have also been criticised for planning to house up to 500 migrants in a barge off the coast of southwest England, with similar sites being planned.

More than 100,000 migrants have crossed the Channel on small boats from France to southeast England since Britain began publicly recording the arrivals in 2018, official figures revealed last Friday.

The route across one of the world's busiest shipping lanes has repeatedly proved perilous, with numerous previous capsizes and scores of migrants drowning in the waters over the last decade.

The years of arrivals have meant Britain's asylum system is facing a huge backlog, with more than 130,000 asylum-seekers still waiting for their applications to be processed at the end of March.

An interior ministry spokesman said Wednesday that the "unacceptable number of people risking their lives by making these dangerous crossings" was putting Britain's asylum system under "unprecedented strain." "Our priority is to stop the boats," he added.

Agence France-Presse