The home secretary is expected to hold talks with her French counterpart about the number of migrants crossing the English Channel to the UK.
Priti Patel and Interior Minister Gérald Darmanin are both due to attend a meeting of G7 ministers in London.
She has warned that Britain could withhold £54.2m it had promised to pay France to help deal with the problem, unless more boats are intercepted.
The Home Office said 785 people crossed the channel in small boats on Monday.
More than 12,600 people have made the dangerous journey so far this year.
The rise in the number of migrants making the crossing in recent days comes after several weeks of unsettled weather.
Patrols stepped up
Back in July the UK agreed to pay France to step up patrols along the French coast in order to deter crossings.
On Tuesday, the prime minister’s official spokesman said UK and French officials were “working on the implementation” of the deal and that “significant” funding provided in November had already led to increased patrols and “enhanced intelligence”.
He said that following a period of poor weather there had been an increase in crossings but warned that the journey remained “extremely dangerous”.
“We remain determined to fix the broken asylum system and break the business model of people smugglers who put lives at risk, and welcome people through safe and legal routes,” he added.
Speaking on Radio 4’s Today programme, Calais MP Pierre-Henri Dumont, said “nothing” can stop migrants crossing the Channel and it is “impossible” for French police to patrol the whole shoreline.
“The fact is, we’ve got 300 to 400 kilometres of shore to monitor every day and every night and it’s quite impossible to have police officers every 100 metres because of the length of the shore” he said.
There are “numerous causes” why people attempt the journey in the first place, including the warmer weather, migrants being more likely to speak English and the perception that it is easier to find work in the UK, he said.
He added: “We have more and more patrols.
“The money that was promised to be given by the UK government to France is set to maintain this number of patrols that we already doubled a few weeks ago.”
Labour’s shadow home secretary Nick Thomas-Symonds called for the government to focus on finding a “workable solution with the French authorities, tackling vile people-smuggling gangs and properly managing safe routes to prevent people risking their lives”.