German hesitation over sending tanks to Ukraine was likely driven by reluctance to take a leading military role rather than practical considerations, but may damage Kyiv's fightback against Moscow, analysts warned.
At a US-hosted donor meeting Friday, newly installed Defence Minister Boris Pistorius insisted Berlin was not hesitating but acting cautiously on the equipment, and said other allies were also weighing the pros and cons.
Berlin is nevertheless facing mounting criticism, from Ukraine itself as well as some European allies, for its failure to drop its block on sending the powerful Leopard 2 tank to Kyiv.
The German-made tank is regarded as one of the world's best, and Kyiv -- currently using Soviet-era models -- has been pleading for it for months.
But Berlin has been wary of sending the tanks to Ukraine -- or approving their export by other countries that use them as required under German law -- apparently out of fear of escalating the conflict.
Ukraine's partners, including Berlin, have supplied and pledged a barrage of armaments for Ukraine, from sophisticated artillery systems to light tanks. But experts believe heavier tanks could make a big difference.
"In terms of Western support to Ukraine thus far, modern main battle tanks are the missing piece in the jigsaw," Ed Arnold, research fellow for European security at British think-tank the Royal United Services Institute (RUSI), told AFP.
"They've already got artillery, air defence, infantry fighting vehicles."
"In terms of being able to ... punch through Russian lines, tanks are key," said Arnold, a former British army and NATO officer.
- 'Join, not lead' -
Yohann Michel, research analyst from think-tank the International Institute for Strategic Studies (IISS), said it was important for Ukraine to restore their tank fleet.
While he said it was "difficult to assess" the number of tanks still available to the Ukrainian armed forces, he added that "obviously it is reducing".
"They need to be able to have a current fleet of vehicles that are actually using the same kind of spare parts, that are using the same kind of ammunition," he said.
There are hundreds of Leopard 2s, first produced in the late 1970s, used by armies across Europe, meaning not only is it easier to get hold of the tank itself, but also spare parts and ammunition.
The IISS said in a recent analysis that around 100 Leopards would be needed to make a "significant" impact, and it would take several weeks to give Ukrainian troops basic training.
There have been concerns it could take some time to deliver the tanks as those that have been in storage for a long time may need to be repaired, while countries will need to keep hold of some for their own defence.
But analysts could see no major technical or practical barriers to stop a coalition of European allies transferring the tanks, pointing instead to German's reluctance to "go it alone" when it comes to supplying arms to Ukraine.
Highlighting this stance, Chancellor Olaf Scholz told US congressmen in Davos this week that Germany would supply tanks to Ukraine if the United States did too.
"The German government prefers to join the ranks than lead the way," Jana Puglierin, from think-tank European Council on Foreign Relations, told broadcaster NTV.
- 'Every day counts' -
Still, the foot-dragging has caused consternation even within the ranks of Scholz's uneasy ruling coalition.
After Pistorius said Friday he had ordered officials to check the country's stocks -- suggesting a transfer had not been ruled out -- Marie-Agnes Strack-Zimmermann, from the right-leaning coalition partner the FDP, reacted with outrage.
"It is shocking that it takes a new minister to check tank stocks, 11 months after the start of the war," she tweeted.
"Now, at the same time as the audit, the training of Ukrainian soldiers on the Leopard must begin immediately. Every day counts."
The delay may be costing Ukraine dearly at a time they are seeking to launch a counteroffensive, warned RUSI's Arnold.
"If Ukraine doesn't have the certainty on whether a) they will have tanks, and b) the numbers of them, then they can't really plan an effective operation to take back their territory," he said.