German Chancellor Olaf Scholz said on Monday he remained convinced of the need to coordinate weapons deliveries to Ukraine with allies as pressure mounts on Berlin to send Kyiv its Leopard 2 battle tanks.
Germany announced last week it would provide Ukraine with Marder infantry fighting vehicles to help repel Russian forces. The announcement came on the same day that the United States pledged Bradley Fighting Vehicles, and a day after a similar announcement from France.
Scholz, who has often underscored the importance of not escalating the conflict in Ukraine or giving Russia a reason to deem it party to the war, said the Western allies had spent "a long time preparing, discussing and organizing this".
Kyiv has also requested heavier vehicles such as the Leopards, which would represent a significant step-up in Western support to Ukraine.
"Germany will not go alone," he said at an event of his centre-left Social Democrat party (SPD) kicking off the campaign for the Berlin state election.
"Germany will always remain united with its friends and allies ... Anything else would be irresponsible in such a dangerous situation."
Germany has become one of Ukraine's top military supporters in response to Russia's invasion after last year overcoming a taboo that is rooted in its bloody 20th century history on sending weapons to conflict zones.
Still, critics say Scholz and his ruling SPD are too slow, waiting for allies to act first instead of assuming Germany's responsibility as the western power closest to Ukraine.
The SPD's junior coalition partners, the Greens and liberal Free Democrats, have been more vocal in their calls to ramp up military support to Ukraine.
Germany cannot rule out the delivery of Leopard tanks, heavier fighting vehicles than the Marders, to support Ukrainian military forces in the future, Economy Minister Robert Habeck of the Greens told German broadcaster ARD at the weekend.
Britain is considering supplying Ukraine with the British Army's Challenger 2 main battle tank, Sky News reported on Monday, citing unnamed sources.
(Reporting by Sarah Marsh and Andreas Rinke; Editing by Alistair Bell)