(Reuters: Moody’s) stated Friday that its credit ratings on Russia and Ukraine were under review by Moody’s. The downgrade was due to Russia’s invasion of Ukraine, which is the most serious attack on a European nation since World War Two.

Russia’s current investment grade rating is “Baa3”. A downgrade of Russia will result in its rating being reduced to “junk”.

Fitch reduced Ukraine’s sovereign rating from B to “CCC” by three notches on Friday. This pushes it into “junk territory.”

Sanctions were imposed by the United States of America and European allies on Russia for some top Russian banks and military exports, as well as members of President Vladimir Putin’s inner circle.

Moody’s stated that there are serious concerns about Russia’s ability manage the disruption caused by new sanctions.

Moody’s rates Ukraine with a B3 rating. A large conflict can pose risks to government’s liquidity, external positions and financial stability.

Russian central banking bolstered its banking sector with billions more foreign exchange and ruble liquidity. It also relaxed a few requirements while the government separately promised full support to companies affected by sanctions.

The central bank and government both stated that Russia’s banking system, which has 300 branches across the country, will continue to be financially stable. Additional tools may be needed.

Russia’s invasion of Ukraine could cause a spate of credit rating downgrades, S&P Global (NYSE:) said on Friday, warning the global economy, and Europe especially, now faced a starkly different picture than expected this year.