The Prime Minister praised the professionalism and bravery of the Armed Forces during a visit to Estonia where he served Christmas lunch to British troops.
Rishi Sunak spoke to UK servicemen and women stationed at the Tapa military base on Nato's flank with Russia, telling them he was "immensely proud" of their "selfless dedication and bravery" and that it would not go unnoticed, including some from The King's Royal Hussars from Catterick Garrison, in the PM's North Yorkshire constituency.
Mr Sunak and his Estonian counterpart, Kaja Kallas, served Christmas lunch to Nato troops and shared mince pies with UK soldiers after dinner.
The Prime Minister apologised that they would be missing the festive period with their families at home and thanked them for their "sacrifice" and "extraordinary" service.
He also listened to their personal accounts of being on Nato's Enhanced Forward Presence across the Baltics during the war in Ukraine.
He said: "This year, we have seen a full-scale war return to our continent, and I am immensely proud of the selfless dedication and bravery of our Armed Forces who responded to that threat to keep the UK and our allies safe.
"As thousands of our military personnel prepare to spend Christmas on deployment, I know that this year of all years we will not take their sacrifice, or the sacrifice of their loved ones, for granted.
"Christmas, after all, is a time for peace, and as alongside our allies, we'll continue to support our Ukrainian and European friends in pursuit of a return of that peace."
More than 12,000 British personnel have been deployed across Europe, partly in response to Russia's invasion of Ukraine in February this year.
The UK temporarily doubled its footprint in Estonia to respond to rising tensions, as part of its commitment to Nato security.
The UK's contribution has also been at sea – the Royal Navy deployed on nine different operations across Europe, involving 31 ships and submarines, six Naval Air Squadrons and 1,750 Royal Marines, in 2022.
Britain also played a leading role in protecting European skies, with around 1,900 UK military flights patrolling, gathering intelligence and providing essential transport, this year.
The UK will deploy Apache and Chinook helicopters to Estonia from January 2023.
The Prime Minister is making a trip to the Baltic region to urge fellow leaders to further support Ukraine, as he pledges a new stream of defensive aid to guard against Russian aggression.