Biden believes Putin has decided to attack Ukraine in coming days

In the coming days, the United States believes that Russian President Vladimir Putin will launch an attack on Ukraine, according to President Joe Biden.

Biden said at the White House that there was reason to believe the Russian forces were planning to attack.

As Russian forces advance on the northern and eastern flank of Ukraine, there is a stunning revelation.

The increased military presence is similar to Russia's annexation of the Black Sea peninsula of Crimea, which caused international uproar and triggered sanctions against Moscow.

Even as Russia has deployed nearly half of its military to the borders of Ukraine, the Biden administration has refused to predict Putin's plan. Biden said there was still time for Putin to choose a path of diplomacy.

Biden reiterated the U.S. commitment to defend NATO allies in the event of a war with Russia.

The United States and our allies are prepared to defend every inch of NATO territory from any threat to our collective security, Biden said.

Collective defense is a principle of the alliance and states that an attack on one NATO country is an attack on all allies.

The Kremlin denied that Russian troops were preparing for an invasion.

Biden approved a new deployment of troops and military equipment to Hungary.

This is breaking news. You can check back for updates.