The Government will provide 12m over three years to help tackle the problem of illegal immigrants in Calais trying to gain entry to Britain.
Home Secretary Theresa May and her French counterpart Bernard Cazeneuve have reached an agreement which will see more co-operation between the British and French law enforcement agencies.
The deal will also involve strengthened security at the port, which has seen an increasing number of migrants using it as a staging post for efforts to cross the English Channel.
In a joint statement Mrs May and Mr Cazeneuve promised to “respond to health emergencies and protect vulnerable people”, in particular victims of human trafficking.
But they insisted the measures would not encourage immigrants to gather in Calais.
The UK will contribute 4m (?5m) a year for three years to a joint intervention fund.
Some of the money will be used to build fences and increase security in the parking area.
Officials from Britain and France will work to improve border controls and new technology could be installed to address the dangers of migrants hiding in tankers and refrigerated lorries.
The statement added: “At the same time, efforts will be made to strengthen operational co-operation by establishing permanent joint mechanisms to deliver promptly the comprehensive action plan and enhance co-operation between British and French law enforcement agencies at the border.
“This will include helping to identify measures to ensure migrants do not breach the laws of either country or threaten the safety of Calais residents or those using the port.
“It will also support improved joint returns initiatives and further comprehensive action against those trying to evade immigration control.”
Information campaigns will begin next month, and these will explain “the reality of illegal migration and its consequences in the United Kingdom” and also provide information on asylum in France or assisted voluntary return.
Police and border agencies in both nations will work together to tackle the organised criminal networks responsible for people smuggling.
The National Crime Agency will second a full-time office to Ocriest, the French agency in charge of tackling illegal immigration.
French border police will send two officers each month to work with the joint border intelligence unit in Folkestone, Kent.
The two ministers also agreed to push for EU action on an “evident migration crisis” in the Mediterranean Sea.