Ratings agencies Fitch and Moody's slashed Russia's sovereign debt on Thursday to "junk" status, or the category of countries at risk of not being able to repay their debt, a week after Moscow began its assault on Ukraine.

Moody's downgraded the rating on Russian long-term debt from Baa3 to B3 subject to a further review over the West's sanctions

China on Thursday denied a report it asked Russia to delay its invasion of Ukraine until after the Beijing Winter Olympics, as international scrutiny grows of warming ties between the two powers.

Beijing has taken a cautious line over the actions of its close ally and President Xi Jinping held a meeting last month with his Russian counterpart where

Russia's Foreign Minister Sergei Lavrov on Thursday accused Western politicians of fixating on nuclear war, one week after Moscow launched its invasion of Ukraine.

"It is clear that World War Three can only be nuclear," Lavrov said in an online interview with Russian and foreign media.

"I would like to point out that it's in the heads of Western