The leaders of US and Germany have been in "lockstep" over their support of Ukraine. And they say they will continue to coordinate military aid. However, German Chancellor Olaf Scholz says the situation has become "very complicated."

On Friday, Scholz visited the White House for the first time since the start of the invasion. US President Joe Biden welcomed him and said that, together, they have made good on their promise to Ukraine. He thanked Scholz for stepping up to provide "critical military support."

Scholz said it is very important they drive home the point that they will continue to support Ukraine for "as long as it takes."

Biden's national security advisor has revealed that Germany agreed to send its Leopard battle tanks only after the US pledged to send its own Abrams tanks. Jake Sullivan said Biden made the decision to accept the condition "in the interest of alliance unity."

However, German officials deny Scholz made such a demand, saying the move was a "joint agreement."

The two leaders have been increasing their pressure on China to refrain from providing any weapons to Russia. Scholz has been calling on the Chinese to use their "influence" to urge Moscow to withdraw troops.

However, China is Germany's biggest trading partner, and US leaders have said they will target Beijing with sanctions if it supports Russia's war efforts.