Russia's invasion of Ukraine has made John Sullivan's tough job as U.S. envoy to Moscow even harder as he grapples with the Kremlin's nuclear saber-rattling and threats to sever relations while keeping his embassy running on one-tenth the normal staff. "It was really bad two and a half years ago," Sullivan remembered of his arrival in Jan. 2020. "It's gotten worse." Severe staff cuts imposed by Russia's government have not yet forced him to clean embassy toilets or buff floors, as rumored in Washington, though he said he knows how to do both. Until now, he said, his meetings with Russian foreign ministry officials have "not been personally insulting or hostile," nor has there been a serious backlash against the embassy. "The security situation here isn't that much different from what it was a month ago, six months ago," he said via video call from a spartan office overlooking an embassy courtyard dusted with fresh snow. "But that could change at the discretion of the host government in a minute." The rivals were engaged in tit-for-tat expulsions and a diplomatic visa feud, with Moscow ordering the closure of the U.S. consulate in St. Petersburg in March 2018. The consulates in Vladivostok and Yekaterinburg were shut after he arrived, leaving the embassy as the only operating U.S. mission in Russia. But its staff has shrunk from some 1,200 in 2017 to around 130, about half of them Marines and other security guards. Implementing a decree by President Vladimir Putin, the Russian government in May 2021 ordered the embassy to fire scores of Russian employees who performed critical tasks. That forced a halt to the processing of all but "life or death" visas. "We're in the Mariana Trench as far as diplomatic relations go," Sullivan said, referring to Earth's deepest ocean abyss. (https://www.usnews.com/news/world/articles/2022-03-31/u-s-envoy-to-moscow-says-russia-ties-sunk-to-mariana-trench-depths) An increase in overnight calls with Washington as tensions mounted over Russia's military build up prompted Sullivan in February to move out of Spaso House, the elegant ambassadorial residence, a 15-minute drive from the chancery and its secure communications facility. He moved into the more modest Townhouse One, where his deputy lived before being expelled, which is a quick walk to the chancery, the U.S. official said. Sullivan said he takes seriously a threat "from the very top of the Russian government" to sever diplomatic ties, asserting that "The Russians don't engage in rhetorical flourishes." "The United States does not want to close its embassy here. President Biden does not want to recall me as ambassador. But that's not something that we necessarily control," he said. Russia expelled Sullivan's deputy in February and recently said another 37 U.S. staffers must leave by July. That would leave the embassy in "caretaker status," secured by a skeleton contingent, one U.S. official said on condition of anonymity. The embassy already has lost its elevator technician, meaning diplomats may soon be doing a lot of stairs, and keeping the sprinkler systems operating will become a serious safety issue if the last two electricians have to leave, the U.S. official said.