British troops will be allowed to fire back at Russian forces if attacked in mission

British troops will be allowed to fire back at Russian forces if attacked as part of a multinational mission to secure any future peace in Ukraine, Western officials have said.

The risk of direct confrontation between the UK and Russia underlines the high stakes of the potential deployment, led by Britain and France.

But whether the operation will ever actually happen in reality remains in serious doubt because of a rather large spanner in the form of Vladimir Putin.

It would require Russia's war in Ukraine to stop and for "peace" to be established before any consideration of what has perhaps rather optimistically been named the "Multinational Force-Ukraine" (MNF-U) heading into the country at the invitation of the Ukrainian government.

Yet, for peace to have been established, it would need a cessation of hostilities - something that would doubtless involve various conditions and compromises agreed between Kyiv and Moscow in the absence of an outright victory by either side.

The idea that the Kremlin would allow for troops from 11 NATO nations to help "secure lasting peace" as part of this negotiation seems fanciful.

The Russian president has repeatedly ruled out such an idea in the past.

Yet London and Paris are still pressing ahead with their preparations - even though some sources have told me that resources would perhaps be better spent focused purely on doing everything possible to ensure Ukraine wins instead of planning for the aftermath.

In the biggest demonstration of preparing for when the war stops, some 300 British troops and more than 2,000 soldiers from 10 other partner nations are taking part in an exercise in Poland that starts on Monday and will last for almost a fortnight.

They will rehearse working together as they prepare for the various roles they might do in any future operation.

This includes deploying fast jets that would help to secure Ukraine's skies and encourage commercial airliners to resume flights. The country's airports have been closed to civilian traffic since the start of Russia's full-scale invasion in February 2022.

At sea, Turkish demining warships will be deployed to make Ukrainian maritime routes safer for commercial vessels.

The focus for land forces will be to train Ukrainians to regenerate the country's fighting strength.

However, because Ukraine has the most battle-hardened and experienced troops in Europe, they will also be sharing their knowledge with their British, French and other European trainers.

Other nations taking part in the Poland exercise - dubbed "Exercise Koalicja" - include Belgium, Estonia, Germany, Lithuania, the Netherlands, Poland, Spain, Sweden and Turkey.

Notably, the US will not be present.

It is not part of the multinational force, though separate US security guarantees for Ukraine will need to be a vital element of any credible peace deal.

A Western official said the multinational force will not be relying on US communications or other systems during the Poland exercise - a sign perhaps of the UK and its European allies seeking to operate without American support.

The training "will test how to move, protect and supply a force that would help rebuild Ukraine's Armed Forces once the fighting ends", the Ministry of Defence said in a statement.

The UK personnel will include soldiers from the British Army's 7 Brigade (the 'Desert Rats').

Defence Secretary Wes Streeting said: "This exercise shows the UK is stepping up, alongside France and our allies, to prepare for the day peace comes to Ukraine. This isn't a hypothetical plan, it's a real force, ready to help Ukraine once the fighting stops."

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Britain stressed the operation is not a NATO mission and will not be undertaking peacekeeping or ceasefire-monitoring duties.

Lieutenant General Tom Bateman is the commander of the multinational force, which is the military wing of what the UK and France call the "coalition of the willing" to support Ukraine.

The British commanding officer said: "The MNF-U will be more ready every day to support Ukraine when the fighting ends, ensuring the Armed Forces of Ukraine are in the strongest possible position to deter future aggression."

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