A total of 235 migrants crossed the Channel by boat on Thursday, setting a new record high for crossings in a single day.
Border Force cutter Seeker and patrol boats Speedwell and Hunter intercepted 17 vessels, one of which was carrying 26 people.
More than 1,100 migrants arrived in the UK in July alone, PA analysis shows.
That figure is almost as high as those of May and June combined.
Thursday’s figure breaks a record set only a week ago, when 202 people crossed in 24 hours.
The French authorities said they had also rescued migrants from several kayaks in their own waters as they headed for the UK.
A helicopter was used in the response that saw at least 23 people intercepted and brought back to France.
According to reports, Home Secretary Priti Patel has ordered a review of the UK’s maritime presence in the Channel, potentially leading to the Navy to be deployed to assist the Border Force.
The Home Office declined to comment on the Navy’s potential involvement.
Minister for Immigration Compliance and the Courts Chris Philp said: “I share the anger and frustration of the public at the appalling number of crossings we have seen today.
“The crossings are totally unacceptable and unnecessary as France is a safe country.
“We work closely with France and I will be in Paris early next week to seek to agree stronger measures with them, including interceptions and returns.
“This situation simply cannot go on.”
He said the only option was to make the route “completely unviable” to deter people from attempting it.
The Home Office has not yet given a breakdown by gender and nationality of those who crossed on Thursday.
Mr Philp said the UK would be returning as many migrants as possible to France and that return flights were scheduled over the coming days.
He added that 22 people smugglers have been jailed in the UK so far this year, and that two more were charged last weekend.
Mr Philp said he met French deputy ambassador Francois Revardeaux on Wednesday to discuss the issue, although the Home Office has refused to provide any further details.
Earlier, it was announced an inquiry has been launched into the reasons behind the huge increase in Channel crossings by migrants.
The Home Affairs Committee in the House of Commons will look at the role of criminal gangs as well as the responses of UK and French authorities to combat illegal migration and support legal routes to asylum.
The committee will also investigate the conditions experienced by people gathered in northern France seeking to enter the UK and they risks they faced during the crossing.
It will also look at migrants’ treatment by the UK authorities upon their arrival in the country, particularly the treatment of unaccompanied children.
Labour’s shadow home secretary Nick Thomas-Symonds accused the Government of a “lack of competence” over migrant crossings.
He said it is “deeply concerning” and said ministers were “failing to get to grips with the crisis”.
Dover MP Natalie Elphicke has met local residents to discuss the issue.
She said on Twitter on Thursday afternoon: “It’s an unacceptable situation and vital that these small boats crossings are brought to an end.”
Mariam Kemble Hardy, head of campaigns at Refugee Action, said the majority of migrants that make the crossing have a valid claim for asylum.
She said: “The Government could easily help put an end to boat crossings by creating more safe and legal routes for people fleeing violence and persecution to find safety here.
“Instead, it has gone quiet over the future of its resettlement programme, one of the few safe and legal routes it offered thousands of refugees every year.”
Refugee Action is calling for the Government to make a long-term commitment to resettling refugees.