Four die trying to board illegal migrant boat in northern France

Over 4,700 crossed channel this year

Southern England lies just 33 kilometres from France at the narrowest point of the channel, and Britain remains a favoured destination for many illegal migrants due to family links, language, and the belief in better employment prospects.

Some 4,776 illegal migrants crossed the channel, one of the world's busiest shipping lanes, between January 1 and April 4, according to UK government data. About 41,500 people crossed it last year.

The influx of illegal migrants has helped drive support for the Reform UK party led by Nigel Farage, a longtime immigration hard-liner. In France, Marine Le Pen's National Rally party has become the single-biggest party in parliament on the back of a tough anti-immigration stance.