WASHINGTON (Reuters) - The United States plans to sanction Russian oligarchs this week under a law targeting Moscow for meddling in the 2016 U.S. election, sources familiar with the matter said on Wednesday, in what could be the most aggressive move so far against Russia’s business elite. 
 
 The action, which could affect people close to President Vladimir Putin, reflects Washington’s desire to hold Russia to account for allegedly interfering in the election - which Moscow denies - even as U.S. President Donald Trump holds out hope for good relations with Putin. 
 
 Trump has faced fierce criticism for doing too little to punish Russia for the election meddling and other actions, and Special Counsel Robert Mueller is probing whether his campaign colluded with the Russians, an allegation the president denies. 
 
 The sanctions, which two sources said would be announced as early as Thursday, would follow the March 15 U.S. decision to sanction 19 people and five entities, including Russian intelligence services, for cyber attacks stretching back at least two years. 
 
 While the steps were the most significant taken against Moscow since Trump took office in January 2017, his decision at the time not to target oligarchs and government officials close to Putin drew criticism from U.S. lawmakers in both parties. 
 
 This week’s actions will include sanctions against Russian oligarchs, including some with ties to Putin as well as to the Russian government, according to two U.S. officials briefed on the deliberations. 
 
 Four sources said the sanctions would be imposed under the Countering America’s Adversaries Through Sanctions Act, also known as CAATSA, which was passed by Republicans and Democrats seeking to punish Russia for its 2014 annexation of Crimea from Ukraine, involvement in the Syrian civil war and meddling in the 2016 U.S. presidential election. 
 
 U.S.-Russian ties have worsened with allegations, which Moscow denies, that Russia was responsible for a March 4 nerve agent attack on a former Russian spy in Britain. On March 26, the United States and several European states announced plans to expel more than 100 Russian diplomats in response. 
 
 The White House and Treasury declined comment on whether they planned to impose sanctions this week. When asked about the issue, a senior U.S. official said: 
 
 “The administration is committed to implementing the CAATSA law as we have said many times. We published an oligarch designation recently and the secretary of the Treasury said further action would be taken. But at this time we don’t have anything specific to announce.” 
 
 Complying with the law, the Trump administration on Jan. 30 published a list of the heads of Russian state-owned companies and “oligarchs,” including such prominent figures as Alexei Miller, the chief executive of Gazprom, and Igor Sechin, the chief executive of Rosneft. ||||| The U.S. flag flies near a Russian flag from the main building of the U.S. Embassy in Moscow on Tuesday as relations between the two countries deteriorate. (Sergei Ilnitsky/EPA-EFE/Shutterstock) 
 
 The United States is expected to impose additional sanctions against Russia by Friday, according to U.S. officials. 
 
 The sanctions are economic and designed to target oligarchs with ties to President Vladimir Putin, the officials said. The final number of Russians facing punitive action remains fluid, the U.S. officials said, but is expected to include at least a half-dozen people. 
 
 In recent weeks, Trump’s national security advisers have pushed for more sanctions after the poisoning of a former Russian spy in England, interference in the U.S. 2016 elections and a cyberattack described as the most destructive and costly in history. 
 
 Officials spoke about the sanctions on the condition of anonymity because they were not authorized to discuss pending actions. 
 
 On Tuesday night, outgoing national security adviser H.R. McMaster called on the United States to take a tougher line against Moscow, saying, “We have failed to impose sufficient costs.” 
 
 The remark came hours after President Trump said in a White House news conference that “nobody has been tougher on Russia than I have.” 
 
 [How Trump got to ‘yes’ on the biggest purge of Russian spies in U.S. history] 
 
 Russian officials, meanwhile, have expressed exasperation with the United States. Moscow’s ambassador to the United States, Anatoly Antonov, said the “atmosphere in Washington is poison.” 
 
 “It’s a toxic atmosphere,” he told NBC News. 
 
 The United States is expected to target individuals on a list of influential Russian political and business leaders that the Treasury Department released in January, officials said. 
 
 The United States could also impose sanctions based on powers granted by Congress to target anyone conducting significant business with Russian intelligence and defense sectors. 
 
 “If they do something tough like this, it may go some distance in reassuring angry members of Congress and the public who are looking at the midterms and wondering if this administration is focused on the Russian threat and taking moves to address it,” said Liz Rosenberg, a former Treasury official who is at the Center for a New American Security. 
 
 White House and State Department spokesmen declined to comment. 
 
 The pending move from Treasury comes as the Trump administration takes an increasingly tough posture toward Moscow at the urging of the president’s senior aides and top U.S. allies. 
 
 Last week, the United States expelled 60 Russian spies and diplomats in response to the poisoning of Sergei Skripal, the former Russian spy, and his daughter, the largest expulsion of Russians in U.S. history. 
 
 In early March, the administration also slapped fresh sanctions on Russian government hackers and spy agencies for interfering in the 2016 election and the cyberattack. 
 
 In recent days, the Trump administration has contemplated additional actions to publicly condemn Russian aggression. Last Friday, the U.S. ambassador to Russia, Jon Huntsman Jr., told administration officials that he wanted to hold a news conference in Moscow about Russia’s expulsion of U.S. diplomats from the country, according to officials familiar with the matter. 
 
 
 
 Ultimately, the administration chose not to hold the news conference for reasons that remain unclear, but Huntsman did appear in a YouTube video explaining Washington’s decision. 
 
 In Congress, the Trump administration continues to face pressure from Russia hawks in both parties to take aggressive action against Putin. In an interview, Sen. Lindsey O. Graham (R-S.C.) said that while he admired the administration’s moves, he believed it had been tried by other administrations and had failed. He said the United States needed to help countries that rely on Russia for oil and gas find new opportunities. 
 
 “We have to hit them by taking away their customers,” he said. 
 
 Philip Rucker contributed to this report.
– President Trump's latest round of sanctions against Russia is going to hit some billionaires with close ties to Vladimir Putin, officials say. Sources tell Reuters and the Washington Post that the new sanctions, expected to be in place by Friday, will target Russian oligarchs under powers given to Trump by the "Countering America's Adversaries Through Sanctions Act." Congress passed the act last year in response to Russia's annexation of Crimea and alleged interference in the 2016 election. The administration, accused by critics of not being tough enough on Russia, imposed sanctions on 19 Russians last month and has joined dozens of other nations in expelling Russian diplomats in response to the poisoning of an ex-spy in Britain. "If they do something tough like this, it may go some distance in reassuring angry members of Congress and the public who are looking at the midterms and wondering if this administration is focused on the Russian threat and taking moves to address it," former Treasury official Liz Rosenberg tells the Post. Sources say the sanctions will target around a half-dozen oligarchs from a list of Russian business and political leaders the administration released earlier this year. CNN reports that the move follows HR McMaster's strong denunciation of Russian aggression in his final remarks as national security adviser. "We have failed to impose sufficient costs," warned McMaster, who has been replaced by John Bolton.