Strengthening Russian-Iranian ties threaten the security not only of Ukraine, but also of Israel, according to senior politicians.

JERUSALEM — Prime Minister Benjamin Netanyahu has long leaned into his relationship with Russian President Vladimir Putin, leveraging it to act as an intermediary between the Kremlin and Washington and to help secure Israel’s northern border with Syria.

What a difference 18 months makes.

Netanyahu returned to power in late December amid expectations that he would pivot Israel in the direction of Russia. He has instead shored up his country’s backing of Kyiv under pressure from Israel’s most significant ally, the U.S. Now he has to weigh alienating Putin by providing defensive arms to Ukraine, a move he has yet to agree to and which Russia has already made it clear would be a red line.

Ukrainian President Volodymyr Zelenskyy publicly asked Israel for its advanced David’s Sling system in his virtual address to the Munich Security Conference on Feb. 17, expressing confidence that Israel would eventually acquiesce.

“We do not have yet the David’s Sling from Israel, but I believe it is just temporary,” Zelenskyy said.

Ukrainian Foreign Minister Dmytro Kuleba also laid out his country’s demands when he met with his Israeli counterpart, Eli Cohen, in Kyiv on Feb. 16.

“Israel knows perfectly well the list of our military and defensive requests which we have provided … to this government, and we will be waiting for some decisions to be taken,” he said. “We are talking about the provision of the Ukrainian skies.”

Cohen, who was the first high-level Israeli official to visit Ukraine since the start of the war, went to Kyiv on a solidarity trip that included a meeting with Zelenskyy, but he left without promising defensive military help.