US President Joe Biden has said that he faced two options following Russia’s offensive in Ukraine: “start a third world war” or hit Russia with economic sanctions. In an interview released on Saturday, Biden insisted that Moscow will pay “a serious price” for its military operation.

“Look, you have two options: start a third world war – go to war with Russia, physically, or two: make sure that a country that acts so contrary to international law pays a price for having done it,” Biden told actor and podcast host Brian Tyler Cohen in an interview posted online on Saturday.

Two days earlier, Biden imposed sanctions on multiple Russian banks, several individuals, and Russia’s tech imports.On Friday, the White House announced it would follow these up with another round of sanctions targeting Russian President Vladimir Putin, Foreign Minister Sergey Lavrov, and members of the Security Council of Russia.

Biden has thus far insisted that the US will not intervene militarily in the conflict between Russia and Ukraine, but has increased military aid to Ukraine and sent thousands of US troops to NATO countries in Eastern Europe.

Immediately before the outbreak of the military actions, Putin warned that any other country interfering in the advance on Ukraine would “face consequences greater than any you have faced in history.”

However, some members of Congress have demanded that Biden go further than sanctions. Following requests from some Ukrainian politicians, Republican Representative Adam Kinzinger, a tacit ally of the Democrat president, has called on Biden to enforce a “no-fly zone” over Ukraine. Such a move would be tantamount to a declaration of war on Russia, critics have warned.