Russia's Presidential office says its military has seized the eastern city of Mariupol in Ukraine. But it says President Vladimir Putin ordered forces not to storm the besieged steel plant, Ukraine's last stronghold in the city. The Ukrainian government has not commented so far.

Russian Defence Minister Sergei Shoigu said, "As for today, all of Mariupol is under the control of the Russian army, the People's Militia of the Donetsk People's republic, and the Azovstal plant territory with the remnants of nationalists and foreign mercenaries is securely blockaded."

Shoigu says the rest of the city has been what he calls "liberated." Putin is hailing it a "success".

Russia says there are still more than 2,000 Ukrainian troops remaining in the plant.

Russian forces have been intensifying their attacks in Mariupol since February 24. They issued an ultimatum demanding Ukrainian forces to surrender but Ukraine denied it.

The country's deputy prime minister accused Russian forces of failing to observe a local ceasefire agreement long enough to allow large numbers of people to leave.

Moscow denies it, blaming Ukraine for not using humanitarian corridors and says Ukrainian troops have continued to retaliate.

In Russia, the military revealed another weapon in its arsenal. It test-launched a new intercontinental ballistic missile capable of carrying multiple nuclear warheads.

Putin says the weapon will provide food for thought for those who try to threaten his country.