The deal, which still needs to be negotiated, comes just months after the two sides resolved the main issue dividing them: trade arrangements in Northern Ireland.
The European Union and the United Kingdom are set to increase cooperation to curb illegal migration in the English Channel.
The announcement was announced on Tuesday following a meeting between British Prime Minister Rishi Sunak and European Commission President Ursula von der Leyen held in Reykjavik, Iceland, on the sidelines of a summit of Council of Europe leaders.
"They agreed to strengthen cooperation between the EU and UK on migration through developing a new working arrangement between UK agencies and Frontex, enabling us to work together on critical operational and strategic challenges including the situation in the Channel," a Downing Street spokesperson said.
"UK and EU teams will now discuss the details and operationalisation of this new working arrangement," they added.
Von der Leyen meanwhile said on Twitter that she "expressed the EU Commission's support for a future UK-Frontex operation working arrangement."
Euronews has reached out to the Commission for more details.
It is the latest sign that relations between Brussels and London are thawing fast now that the thorny issue of trade arrangements for Northern Ireland was resolved through the Windsor Agreement reached in late February and signed a month later.
The migration deal, which still needs to be negotiated, comes after the governments of Belgium, France, Germany, the Netherlands and the UK called in December for an EU-UK cooperation agreement on migration "in order to tackle irregular migration in north-western Europe".
Paris and London, meanwhile, struck another deal in March under which the UK will provide funding to the French government (€141 million in 2023-24, €191 million in 2024-25 and €209 million in 2025-2026) to increase the number of officers and patrols on the French coast, to pay for new capabilities including drones and to operate a new command centre and a new detention centre.