Ukraine's new Nato-provided Leopard 2 tanks will be serviced and repaired at a complex in Poland, it was announced on Friday.
Defence ministers from Ukraine, Poland and Germany agreed to the plan during talks at Ramstein, a US airbase in Germany.
Ministers from dozens of countries were holding talks on arming Ukraine a day after Nato Secretary General Jens Stoltenberg visited Kyiv.
Several nations are providing German-made Leopard 2s from their arsenals after Berlin gave approval in January.
Western allies hope the tanks could help Ukraine regain territory from Russia in an expected spring counter-offensive.
"I'm confident that they will now be in a position to be able to liberate even more land," Mr Stoltenberg said.
Germany is keen to protect its tank donations by improving Ukraine's air defences and contributing to maintenance.
"Every piece of material that we are delivering in this war ... wears out, especially when it is in continuous service in battle," said German Defence Minister Boris Pistorius.
"Near the Polish-Ukrainian border, it will be ensured that these tanks can quickly be refurbished and repaired when there is a need — and the need will rise."
Russian President Vladimir Putin "cannot play for time ... we will stick it out," said Mr Pistorius.
Germany said training for Ukrainian troops on older Leopard 1 models would begin imminently.
Nato commanders are considering whether US-made Patriot air defences should continue to be stationed in Poland or return to Germany to join a high-readiness force.
The meeting at Ramstein was the 11th since the coalition known as the Ukraine Defence Contact Group first met a year ago.
US Defence Secretary Lloyd Austin said it had provided more than $55 billion in security assistance for Ukraine since.
But Ukraine still "urgently needs our help to shield its citizens, infrastructure and forces from Russia's missile threat," he said.
Kremlin spokesman Dmitry Peskov accused Nato of trying to "absorb and drag Ukraine into the alliance", showing Russia was right to "launch this operation" to ensure its security.
Britain's Ministry of Defence said it had committed to give Ukraine more than 300,000 artillery shells this year.
The UK has delivered more than 150 armoured vehicles and 32 AS90 self-propelled guns, it said.
"The message from Ramstein is clear," said Defence Secretary Ben Wallace. "International support for Ukraine is growing. More countries than ever are attending. Donations are increasing and their delivery is accelerating."
Ukraine, which is lobbying for Nato membership, said it had won a promise that it could work with an allied procurement agency.
Mr Stoltenberg on Friday said Nato countries agree that Ukraine should one day become a full member of the alliance.
He said that once the war ends, Ukraine should have “the deterrence to prevent new attacks”.
Mr Stoltenberg met Ukrainian President Volodymyr Zelenskyy on Thursday on his first visit to the country since Russia launched its invasion last year.
