Britain and France have set out plans for Exercise Koalicja, a military exercise in Poland later this month, the Guardian reports. It will rehearse how European forces could deploy quickly to Ukraine if the war ends.

The exercise will involve 2,800 soldiers, sailors and aviators, the Guardian reports. France is sending 1,500 troops and Britain 300, the Guardian says.

Troops will practise moving people and kit into Poland, the Independent reports. They will also run joint drills and fly jets and a refuelling plane.

Western officials said British troops and their allies could fire back if attacked while keeping the peace in Ukraine, the Guardian reports. "Clearly we will protect our forces against any aggression," an official familiar with the plans said. The official stressed that the troops would act in a way that was "defensive in nature," the Guardian says.

The force would not rely on US systems or technology such as Starlink, officials said, according to the Guardian. "We are not dependent on US systems," one official said.

Lt Gen Tom Bateman leads the force. He said the countries were committed "to providing robust and binding security guarantees for Ukraine following a cessation of hostilities," the Guardian reports.

If deployed after a ceasefire, the force would help rebuild Ukraine's armed forces and help clear mines in the Black Sea, Bateman said, according to the Independent.

"This exercise shows the UK is stepping up, alongside France and our allies, to prepare for the day peace comes to Ukraine," British Defence Secretary Wes Streeting said, the Independent reports.

All of the European countries involved say they will deploy only once fighting stops, the Independent reports. Some experts say the mission may never take place, it says.