A bipartisan group of US senators also promised weapons to Ukraine, which could include missiles, small arms and boats, to help the country defend itself from a potential invasion amid a Russian military build-up on its borders.

German Chancellor Olaf Scholz, however, has stressed Berlin's policy of not supplying lethal weapons to conflict zones.

"I can understand the wish to support Ukraine, and that's exactly what we are doing already," Lambrecht said in an interview published on Saturday in the Welt am Sonntag.

"Ukraine will receive a complete field hospital together with the necessary training in February, all co-financed by Germany for 5.3 million euros ($A8.4 million)," she said, noting that Germany has been treating severely injured Ukrainian troops in its military hospitals for years.

But Berlin was not ready to supply Kyiv with weapons for the time being, the minister said.

"We have to do everything to de-escalate. Currently, arms deliveries would not be helpful in this respect. There is agreement on this in the German government," Lambrecht said.

With her remarks, she sided with German Foreign Minister Annalena Baerbock, who said Germany would not criticise other countries for being ready to supply weapons to Ukraine.

"But I don't think it is realistic that such deliveries could tip the military balance," Baerbock told Sueddeutsche Zeitung.

"The most powerful weapon ... is for NATO allies, EU member states and the G7 to make it clear (to Russia) that every fresh aggression will be answered with massive consequences."

Australian Associated Press