WASHINGTON

US President Joe Biden said Russian President Vladimir Putin is not doing well in Ukraine as the war waged by Moscow nears the eight-month mark.

"I think that Vladimir Putin finds himself in an incredibly difficult position," Biden said during a news conference about gas prices.

"What reflects to me is it seems his only tool available to him is to brutalize individual citizens in Ukraine, Ukrainian citizens, to try to intimidate them into capitulating," he said.

Biden's remarks came hours after Putin signed a decree on the introduction of martial law in the Donetsk, Kherson, Luhansk and Zaporizhzhia regions -- recently annexed from Ukraine.

Kyiv's forces have made advances in recent weeks, while Moscow called up more reservists and launched new attacks in Ukraine, including that nation’s capital of Kyiv, following an explosion on a strategic bridge linking Russia to Crimea, which it illegally annexed in 2014.