Russian officials have lashed out at the United States over the upheaval in Venezuela, vowing to support embattled President Nicolas Maduro and sharply criticizing Washington for imposing sanctions on the Venezuelan state oil company PDVSA.In comments on January 29, Foreign Minister Sergei Lavrov accused Washington of "publicly setting a course for illegal regime change" by recognizing opposition leader Juan Guaido as Venezuela's interim president.He did not outline any specific steps in support of Maduro's government.In separate but almost simultaneous remarks, President Vladimir Putin's spokesman declined to comment when asked whether Russia would send military aid if the U.S. military gets involved in the crisis in Venezuela.His remarks came after U.S. National Security Adviser John Bolton appeared at a White House briefing on January 28 holding a notepad with the words "5,000 troops to Columbia" scribbled on the page, sparking speculation about U.S. intentions.Two days earlier, Peskov sought to cast doubt on a Reuters news agency report that as many as 400 private Russian military contractors had been sent to bolster security for Maduro.In his comments on January 29, Peskov also said that the U.S. sanctions against PDVSA amounted to illegal interference in Venezuela's internal affairs, and that Russia would use all the legal mechanisms at its disposal to protect its interests there.The sanctions, imposed on January 28, prohibit PDVSA from collecting proceeds from crude oil sales to U.S. refineries, adding to the pressure on Maduro.Bolton said on January 28 that the sanctions would cost Maduro $11 billion in lost export proceeds over the next year and block him from accessing PDVSA assets worth $7 billion.In a defiant broadcast on national television later the same day, Maduro said he would take legal action to challenge the sanctions and defend Citgo Petroleum, PDVSA's U.S. refining subsidiary, which he accused the United States of trying to steal.Russian state oil giant Rosneft, which operates in Venezuela and has issued loans to PDVSA, said that the company owed it $3.1 billion at the end of the third quarter of 2018.The activity of Rosneft, headed by longtime Putin associate Igor Sechin, is a major element in Moscow's close ties with Venezuela.Russia has poured money into the South American country, whose leaders have been deeply at odds with Washington since Maduro's predecessor, the late socialist leader Hugo Chavez, came to power 20 years ago,The Russian government and Rosneft have provided Venezuela with at least $17 billion in loans and credit lines since 2006, and a senior Russian official said on January 29 that Caracas will have trouble servicing its sovereign debt to Moscow."There will probably be problems. Everything now depends on the army, on the soldiers and how faithful they will be to their duty and oath. It is difficult, impossible to give a different assessment," Deputy Finance Minister Sergei Storchak told reporters., but Bolton suggested that could change."Our assessment...is that the rank and file of the Venezuelan military is acutely aware of the desperate economic conditions in the country and we think they look for ways to support the National Assembly government," he said, referring to Guaido.Guaido has rejected accusations from Maduro and Moscow that the United States is staging a coup, arguing that Venezuelan citizens are simply exercising their constitutional rights.The head of the opposition-controlled National Assembly, Guaido proclaimed himself Venezuela's interim president before thousands of supporters last week.He has been recognized as the Latin American country's rightful leader by two dozen nations that say Maduro's May 2018 reelection was illegitimate because his strongest opponents were barred from running.Meanwhile, the UN human rights office said that security forces in Venezuela detained about 850 people last week amid antigovernment protests, including nearly 700 on January 23.Speaking in Geneva on January 29, rights office spokesman Rupert Colville said that more than 40 people are now believed to have been in killed "in different manners" amid the recent protests.With reporting by Interfax, Reuters, TASS, AFP, AP, and USA Today