Watch: Huge fireball explodes after missile hits gas pipeline in Ukraine

Video has emerged of a huge fireball erupting after a missile hit a gas pipeline in Ukraine.

There was heavy fighting for Ukraine’s second city, Kharkiv, in the northeast, overnight where Russian troops blew up a natural gas pipeline, a Ukrainian state agency said.

That blast sent a mushroom cloud up into the darkness.

Ukraine’s gas pipeline operator said the transit of Russian gas to Europe via Ukraine was going on as normal.

Another bomb hit an oil terminal in Vasylkiv, southwest of Kyiv, the town’s mayor said.

Blasts sent huge flames and billowing black smoke into the night sky, online posts showed.

“The enemy wants to destroy everything,” said the mayor, Natalia Balasinovich.

Russian-backed separatists in the eastern province of Luhansk said a Ukrainian missile had blown up an oil terminal in the town of Rovenky.

Fighting has erupted in Kyiv with blasts and gunfire heard through the night.

Three blasts after air raid sirens went off shortly before 9am

President Volodymyr Zelensky was ever defiant in a video message posted to his social media.

“We have withstood and are successfully repelling enemy attacks. The fighting goes on,” he said.

A US defence official said Ukraine’s forces were putting up “very determined resistance” to Russia’s air, land and sea advance, which has sent hundreds of thousands of Ukrainians fleeing westwards, clogging major highways and railway lines.

The United States and its allies have imposed a range of sanctions on Russia.

On Saturday, they moved to block certain Russian banks’ access to the Swift international payment system.

They also said they would impose restrictions on Russia’s central bank to limit its ability to support the rouble and finance Putin’s war effort.

“We are resolved to continue imposing costs on Russia that will further isolate Russia from the international financial system and our economies,” said a statement from the United States, France, Germany, Canada, Italy, Britain and the European Commission.

After initially shying away from such a move largely because of concern about the impact on their economies, the allies said they committed to “ensuring that selected Russian banks are removed from the Swift messaging system.”

They did not name the banks that would be expelled, but an EU diplomat said some 70% of the Russian banking market would be affected.

A Ukrainian presidential adviser said about 3,500 Russian soldiers had been killed or wounded. Western officials have said intelligence showed Russia suffering higher casualties than expected.

Russia has not released casualty figures and it was impossible to verify tolls or the precise picture on the ground.

At least 198 Ukrainians, including three children, have been killed and 1,115 people wounded.

Ukraine, a democratic nation of 44 million people, won independence from Moscow in 1991 after the fall of the Soviet Union and wants to join NATO and the EU, goals Russia opposes.

Putin has said he must eliminate what he calls a serious threat to his country from its smaller neighbour, accusing it of genocide against Russian-speakers in eastern Ukraine - something Kyiv and its Western allies reject as a lie.