ITV News Correspondent Martha Fairlie on the record numbers taking the precarious journey across the Channel to Kent
ITV News understands Monday could have seen the highest number of people attempting to cross the English Channel in a single day.
The Border Force is expected to confirm Monday's figure on Tuesday.
A packed lifeboat was pictured arriving on a beach in Dungeness in Kent.
While officials led passengers away, one woman was seen clutching a small baby who was strapped to her.
Images show other young boys and girls being carried or escorted to safety among several men and women.
Crossings in 2021 – which already eclipsed last year’s annual total last month – have resumed in recent days following a period of bad weather.
Eyewitnesses described authorities including Border Force, and the RNLI, as appearing to be very busy as a steady stream of crossings was thought to be under way amid calm waters and sunny skies.
Sunday saw the first small boat crossings for more than two weeks due to bad weather.
Some 158 people, including five children, arrived on Dover from four boats.
Those arrivals brought the total number of people who have crossed to the UK aboard small boats this year to more than 12,500, according to data compiled by the PA news agency.
Prime Minister Boris Johnson said Home Secretary Priti Patel is "working around the clock" to ensure France impedes the passage of illegal migrants across the Channel.
He was answering a question by Conservative MP Jacob Young (Redcar), who argued Britain’s ability to provide Afghans a safe passage to the UK is strained by "the continuing uncontrolled illegal migration on the English Channel".
Mr Johnson said: "My honourable friend is completely right and, of course, the issue is that very sadly I think our friends across the Channel in France are faced with a very difficult problem."
He added: "A large number of people want to come to this country, and we are doing everything we can to encourage the French to do the necessary and impede their passage."
"But I know the Home Secretary is working right around the clock to ensure that we not only encourage the French to stiffen their sinuses and stop people making the journey, but we use every possible tactic available to us as well."
Crossings in 2021 have already eclipsed last year’s annual total of 8,417 and that tally continues to rise on fair weather days.
Despite this, the UK continues to see far fewer boat arrivals and asylum claims than many of its European counterparts.
Earlier this year the RNLI saw a large spike in donations after the charity’s chief executive defended its role in rescuing people crossing the English Channel, describing it as "humanitarian work".
It came after the charity said it had faced heightened criticism for rescuing migrants, with one crew having to call the police after being subjected to abuse.