WASHINGTON, Oct 31 (AFP) - The US secretaries of state and defence urged Congress on Tuesday (Oct 31) to sustain support for Ukraine and warned that Russian President Vladimir Putin wants to use the Israel-Hamas war to reduce Western support for Kyiv.

President Joe Biden has combined military aid for Ukraine and Israel in a proposed US$106 billion package, but a significant number of Republicans in Congress - among whom support for Ukraine's fight against Russia's invasion is faltering - are opposed to linking the two.

"I can guarantee you that without our support, Putin will be successful," Defense Secretary Lloyd Austin told a Senate hearing on the supplemental funding request.

"If we pull the rug out from under them now, Putin will only get stronger and he will be successful in doing what he wants to do in acquiring his neighbour's sovereign territory," he said.

Washington is by far the biggest donor of military aid to Ukraine, committing some US$43.9 billion since Russian forces invaded in February 2022 - assistance that has helped Kyiv regain ground seized by Moscow.

But Republican opposition has put future assistance for Kyiv in doubt, and the US government has had to rely on previously authorised aid in the absence of new funding from Congress.

Secretary of State Antony Blinken told the same hearing that a halt to US assistance for Ukraine could encourage other countries to follow suit.

"This is an instance where we've seen very significant burden-sharing that would almost certainly go away if we go away," he said.