By Katharine Jackson (Reuters) -U.S. Senate Democratic leader Chuck Schumer said on Sunday he would act on a Biden administration request to add provisions to a $33 billion Ukraine aid package to allow the United States to seize Russian oligarchs’ assets and send money from their sale directly to Ukraine. “Ukraine needs all the help it can get and, at the same time, we need all the assets we can put together to give Ukraine the aid it needs,” Schumer said at a media briefing in New York City. President Joe Biden asked Congress to approve $33 billion in assistance for Kyiv on Thursday in what w…