WASHINGTON, 01 January 2022, (TON): President Joe Biden warned his Russian counterpart Vladimir Putin of a tough US response to any invasion of Ukraine, while the Kremlin leader said anti-Moscow sanctions would be a “colossal mistake.”

After a 50 minute phone call their second in just over three weeks both presidents indicated support for further diplomacy on the tense standoff between Russia and Western-backed Ukraine.

Putin was “pleased” overall with the talks, foreign policy adviser Yury Ushakov told reporters. A senior US official, who spoke on condition of anonymity, said the tone “was serious and substantive.”

But there was no disguising the depth of disagreement or the dangerously high stakes on the fringes of eastern Europe ahead of in-person negotiations between high-ranking Russian and US officials on January 10.

Press Secretary Jen Psaki said in a statement “Biden made clear that the United States and its allies and partners will respond decisively if Russia further invades Ukraine.”

Ushakov, referring to Washington’s repeated threats of economic sanctions as a response to a Ukraine attack, said this would be “a colossal mistake. We hope this will not happen.”