Two boats carrying 40 migrants including children have been intercepted in the Channel, according to the Home Office.
The boats were stopped by Border Force vessels off the coast of St Margaret's Bay, Kent, on Saturday morning.
A Home Office spokeswoman said the migrants told officials they were from Pakistan, Iraq and Afghanistan.
They were medically assessed and will now be interviewed by immigration officers.
Charlie Elphicke, the MP for Dover, urged action to "prevent a summer of chaos in the English Channel".
The Home Office spokeswoman said: "Anyone crossing the Channel in a small boat is taking a huge risk with their life and the lives of their children.
"It is an established principle that those in need of protection should claim asylum in the first safe country they reach and since January more than 35 people who arrived illegally in the UK in small boats have been returned to Europe."
Two cutters have been returned from overseas since the Home Secretary declared a major incident in December and a joint action plan was also agreed with France.
Mr Elphicke said "more migrants have arrived so far this year than arrived in the whole of last year" and described the situation as a "crisis".
"The Home Office needs to regain control of our borders and seek a proper agreement with the French to stop these people leaving the French coast," he said.
"This is not just about border security. We've got to stop vulnerable people being exploited by criminal trafficking gangs.
"And protect life - these are overcrowded boats with men, women & children aboard.
"There is a real risk of a tragedy in the middle of the English Channel resulting in loss of life."
