Will the devastating attack on Israel by Hamas militants detract from international support for Kyiv?

It's a question that is on the mind of Ukraine's President Volodymyr Zelensky, who has expressed concern in recent days that the answer might be yes.

Those worries come on top of uncertainty over the long-term future of US aid for Kyiv due to opposition from hardline Republican lawmakers, which led Congress to drop new funding for Ukraine from a recent bill.

Zelensky — who visited Brussels Wednesday for a meeting of Ukraine's international supporters — said his question for them was whether assistance will lessen.

"The partners say no. But who knows how it will be? I think nobody knows," he said.

The Ukrainian leader also voiced similar worries in a recent interview with the France 2 broadcaster, saying: "There is a risk that international attention will turn away from Ukraine, and that will have consequences."

Despite his concerns, Zelensky has repeatedly expressed support for Israel following the multi-pronged Hamas attack from Gaza that the Palestinian militant group launched Saturday, which has left thousands of people dead.

The assault sparked widespread international condemnation and rapid action by Washington, which sent an aircraft carrier and other warships to the eastern Mediterranean and promised munitions and other equipment to Israel.

But US Defence Secretary Lloyd Austin and other American officials say this does not mean support for Ukraine will suffer.

"In terms of our ability to continue to support both the efforts in Ukraine and… the efforts in Israel as well, absolutely — we can do both, and we will do both," Austin said Wednesday in Brussels.

Zelensky later said in his daily address that he had been assured the United States "will continue to provide Ukraine with the constant and uninterrupted support necessary for its defense."

Shifting attention from Ukraine