Germany will not send fighter jets to Ukraine, Chancellor Olaf Scholz repeated on Sunday, as Kyiv increased calls for more advanced weapons from the West to help repel Russia's invasion.
After weeks of intense debate and mounting pressure from allies, Mr Scholz agreed on Wednesday to send 14 Leopard 2 tanks to Ukraine and to allow other European countries to send theirs.
"I can only advise against entering into a constant bidding war when it comes to weapons systems," Mr Scholz told the Tagesspiegel newspaper.
"If, as soon as a decision [on tanks] has been made, the next debate starts in Germany, that doesn't come across as serious and undermines citizens' confidence in government decisions."
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Ukrainian President Volodymyr Zelenskyy thanked Berlin and Washington for the move, which was regarded as a breakthrough in efforts to support the war-torn country.
But Mr Zelenskyy immediately stressed that Ukraine needed more heavy weapons from Nato allies to fend off Russian troops, including fighter jets and long-range missiles.
Mr Scholz warned against raising "the risk of escalation", with Moscow already condemning the tank pledges.
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"There is no war between Nato and Russia. We will not allow such an escalation," he said.
Mr Scholz said it was "necessary" to continue speaking with Russian President Vladimir Putin. The last phone call between the leaders was in early December.
"I will talk to Putin by phone again," he said.
"But of course, it's also clear that as long as Russia continues to wage war with unabated aggression, the current situation will not change."