By Trevor Hunnicutt
WASHINGTON (Reuters) -President Joe Biden is expected to unveil new sanctions targeting Russia's economy this week, according to a U.S. official, as part of measures to bolster Kyiv's war effort against Moscow before Donald Trump takes office.
Separately, the Biden administration announced $500 million in new military aid for Ukraine on Thursday that included air defense missiles, air-to-ground munitions and support equipment for F-16 fighter jets.
President-elect Donald Trump's return to the White House on Jan. 20 has sparked hope of a diplomatic resolution to end Moscow's invasion but also fears in Kyiv that a quick peace could come at a high price for Ukraine.
Advisers to Trump have floated proposals to end the war that would effectively cede large parts of the country to Russia for the foreseeable future.
Biden aides say they want to put Ukraine in the strongest position on the battlefield to give them leverage for possible negotiations with Russia this year.
There were no immediate details on the sanctions Biden would impose in his final days in office but Biden aides are briefing Trump's aides on the steps they are taking, the official said.
Reuters reported earlier this week that three sources said the United States was planning more sanctions targeting Russia's oil revenues that help fund its war on Ukraine. One of the sources said the sanctions would target two Russian oil companies, more than 100 tankers, oil traders and Russian insurance companies, without naming the entities.
The U.S. official said that most of the weapons and munitions promised to Ukraine have been delivered and the remainder are on the way. Ukraine's critical munitions stock piles are now in a healthy position, the official added.
Outgoing U.S. Defense Secretary Lloyd Austin, in a statement, noted that the latest aid comes as he meets with about 50 allies at Ramstein Air Base in Germany.
Secretary of State Antony Blinken said separately that the group would "stand united to ensure Ukraine has the capabilities it needs to defend itself against Russia’s aggression". But German officials were bracing for a possible U.S. withdrawal from the meetings under Trump.
Ukrainian President Volodymyr Zelenskiy's government has regularly pushed for greater weapons support than Biden was initially willing to offer but ultimately did, leading to tense private encounters over topics including Abrams tanks, F-16 fighter jets and longer-range ATACMS missile systems.
In retrospect, the U.S. official said, none of those steps have yielded major gains for Ukraine on the battlefield.
Ukraine may need security commitments, including potential NATO membership, to ward off a future Russian assault following peace negotiations, the U.S. official said. Russia launched its full-scale invasion of Ukraine in February 2022.
Meanwhile, U.S. military officials are studying North Korean operations in the Ukraine war to assess how they might handle any conflict in Asia. Thousands of North Korean forces are believed to be supporting Russians in the war with Ukraine.
The United States is also likely to impose sanctions on more Chinese entities for their efforts to support Russia, the official said.