After months of apparent reluctance, Germany confirmed plans to send tanks to Ukraine, aid Kyiv hopes will change the game on the battlefield. What about the US?
US President Joe Biden's administration is expected to announce plans soon to deliver at least 30 M1 Abrams tanks.
German Chancellor Olaf Scholz confirmed his country decided to send at least 14 Leopard 2 tanks. Germany has also allowed the export of its tanks via third countries to Ukraine.
The Russian ambassador to the US condemned the news as "another blatant provocation".
So far, the US and Germany have always resisted internal and external pressure to send tanks to Ukraine.
Washington said it needed extensive training and maintenance for the high-tech Abrams tank.
Meanwhile, Berlin expressed caution so that NATO does not become a party directly involved in the war with Russia.
Citing anonymous sources, the US media outlet reports that an announcement regarding the transfer of Abrams to Ukraine could come as soon as Wednesday (25/01).
An unnamed official was quoted as saying at least 30 combat vehicles could be delivered.
However, any potential delivery timelines remain unclear, and it could take months or even years for US combat vehicles to reach the battlefield.
According to US media reports, German officials privately insisted they would only approve the delivery of the Leopard 2 to Ukraine if the US also delivered the M1 Abrams.
"If Germany keeps saying they will only send or release the Leopards on the condition that America sends the Abrams, we have to send the Abrams," Democratic Senator Chris Coons, one of Biden's partners, told Politico on Tuesday (24/01).
Britain has already said it will send Challenger Two tanks to Ukraine.
Poland this week also expressed an intention to send Leopard 2 tanks to Ukraine, but the tanks are made in Germany so Berlin will need to approve their export.
At least 16 European and NATO countries have Leopard 2 tanks, according to the International Institute for Strategic Studies.
Not all of them are going to send tanks to Ukraine - but Scholz's clear decision now means they can do so, if they want.
What weapons were sent to Ukraine?
Germany's decision to deliver the Leopard 2 tanks came after intense pressure from a number of international allies as well as Ukraine itself.
Ukrainian President Volodomyr Zelensky says his troops urgently need Western battle tanks, to defend his territory against Russian attacks and push Russian troops out of occupied areas.
Some Western officials also believe that Russian forces are currently in a weak position, and that there is a window of opportunity where more advanced tanks could help Ukraine advance.