A bus that has been converted into a field hospital has been presented to the Ukrainian ambassador.
The single-decker has covered more than 500,000 miles (804,000 km) and was refitted by Swindon Humanitarian Aid Partnership (SHAP).
It will now be taken to Ukraine and used in areas affected by fighting.
"If it saves one life it will have been worthwhile and my sense is it may save many more," said SHAP's chairman Mike Bowden.
The vehicle was handed over to ambassador Vadym Prystaiko outside the House of Lords in London.
It was originally donated by Swindon's Bus Company and the seats were removed and replaced by three hospital beds, as well as other equipment including heart monitors, defibrillators and fresh water tanks.
It is being described as a mobile medical unit and will be used to treat ill or injured people.
SHAP was formed by Ukrainian, Polish, Lithuanian and British people living in Wiltshire to help those still in Ukraine and those seeking refuge in the UK after Russia's invasion.
Speaking about his country's need for the vehicle, ambassador Mr Prystaiko said: "There is a gap between the frontline and the hospital, and that's what we need right now, to evacuate people and provide them with the necessary help on the way."
He added that he and the whole Ukrainian nation were touched by the support they had received from people in the UK.
The next challenge will be physically transporting the bus to Ukraine.
The RAF said it was not cost effective to fly it out, so it will most likely be driven the approximately 2,000 miles (3219 km) to where it is needed, although SHAP estimates that could cost £1,000 in diesel.
Another bus is already awaiting conversion, this time into a play space for children.