Britain and France have agreed to boost bilateral cooperation over a spike in migrants trying to cross the Channel, the UK's Home Office said Sunday.

In the coming weeks, the two countries will increase surveillance patrols and focus on measures to dismantle trafficking gangs and improve awareness about the dangers of sea crossings in one of the world's busiest shipping lanes.

"The UK and France will build on our joint efforts to deter illegal migration - protecting our borders and human life," said Britain's Home Office minister Sajid Javid, after speaking on the phone with French counterpart Christophe Castaner.

Attempts to cross the English Channel have been increasing since October, with authorities on both sides struggling to stop them.

Javid, who has previously said the rise is being treated as a "major incident", has faced criticism from the opposition and from within his own party for responding too slowly.

"More than 200 migrants have arrived on the Kent coast in small craft in the past two months. The scale of the problem is unprecedented," Charlie Elphicke, the MP for Dover on the southeast coast of England, told the Daily Mail.

A particular increase in arrivals has been recorded over the Christmas period, with British authorities finding 43 people in English waters on Christmas Day and December 26.

On Thursday, British border officials found 23 Iranians in three locations in Kent on England's southeast coast, hours after French maritime authorities intercepted 11 migrants in a small boat near Sangatte.

And on Sunday, authorities intercepted six Iranians near Kingsdown beach in Dover.