Switzerland on Thursday condemned "in the strongest terms" the attack on a humanitarian warehouse in the Ukrainian coastal city of Mariupol.

The attack against the International Committee of the Red Cross (ICRC) is "a serious violation of international humanitarian law," Swiss President Ignazio Cassis told journalists gathered for an international cooperation summit in Geneva on Thursday.

"It is simply unacceptable," as are indiscriminate attacks on civilians, he added.

An ICRC warehouse has been targeted by Russian shelling in Mariupol in recent days although the building was clearly demarcated with a red cross.

The Swiss-run organisation no longer has staff in the besieged city.

“We distributed all of the supplies from the warehouse earlier in March,” the ICRC said in a March 30 statement. “This included medical supplies to hospitals and relief supplies to people living in shelters.”

The ICRC has had to deal with misunderstandings about its neutral role in the crisis after its president, Peter Maurer, visited Russia.

Sanctions justified

Cassis on Thursday said Switzerland’s sanctions against Russia were justified as inaction would have meant helping “the aggressor”.

Russia launched a full-scale aggression on its neighbour on February 24, the biggest attack by one European nation against another since the Second World War. Europe has absorbed more than 4 million Ukrainian refugees because of the crisis.

Switzerland would continue to help Kyiv in the coming years, Cassis said, provided “Ukraine remains an independent country.”

The impact of the conflict will be felt “for decades”, he warned, and is completely changing the European approach to security.

Switzerland, for now, is focusing its efforts on delivering humanitarian assistance and the search for a ceasefire.

Cassis promised to work "actively" to ensure that the world "comes out of this horrible war" in Ukraine. He stressed the readiness of Swiss good offices. "We are ready" to contribute to peace, he said.

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