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German Chancellor Olaf Scholz offered an unusually animated defence of his policy towards Ukraine, rebuffing critics who say his military support has been too slow as well as pacifist dissenters who say no arms should be sent at all.
Mr Scholz won plaudits for facing down a crowd of hecklers who whistled and shouted anti-weapons slogans at an International Workers' Day rally on Sunday, telling them their views were outdated.
“I respect any pacifism and any opinion. But it must seem cynical to citizens of Ukraine if they are told they should defend themselves against Putin's aggression without weapons,” he shouted over the protesters.
“We will not allow borders to be pushed aside or territory to be conquered with violence,” he said at the event in Duesseldorf.
The typically reserved Mr Scholz has been under pressure over what Ukraine regards as half-hearted military support from Berlin and what the opposition has called a lack of clarity about his policies. Some MPs in his own ranks have expressed frustration with the pace of military support.
Although the latest figures show Germany is one of the main providers of financial aid to Ukraine's military, it lags behind many of its allies in direct arms and weapons shipments to defend against Russia.
Mr Scholz separately sought to deflect that criticism by telling the newspaper Bild am Sonntag that he was acting in co-ordination with allies and that he was “suspicious of hasty action and of Germany going it alone".
MPs last week voted to approve the export of heavy weapons such as tanks to Ukraine, a move away from Germany's cautious stance that was welcomed by allies including the US.
Russia's invasion of Ukraine has prompted soul-searching in Mr Scholz's party and the wider political class about a years-long conciliatory stance towards Moscow that ultimately failed to bring peace.
But Mr Scholz is at the same time having to fend off criticism from those such as the Workers' Day peace protesters who say Germany's involvement is going too far, although polling suggests this is a smaller group.
The hecklers at the Duesseldorf event urged Mr Scholz to “make peace without weapons”, using a slogan that rhymes in German and has a long history in German peace activism.
A group of 28 self-described artists and intellectuals wrote an open letter to Mr Scholz last week urging the chancellor to stand by his initial wariness of provoking Russia rather than changing tack to arm Ukraine more heavily.
They said that Nato powers such as Germany would bear responsibility along with Russia if the conflict were to escalate into what they described as a Third World War.
The letter drew criticism from politicians and others who said it was calling for a Ukrainian surrender and was naive to suggest that Russia could be kept in check by appeasement.
“The fact that the signatories still haven't understood that Vladimir Putin doesn't need a rational motive for his criminal actions is so detached from reality that you start to question the term 'intellectuals',” wrote German commentator in Kyiv Denis Trubetskoy.