What you need to know about Ukraine crisis

Here's what you need to know about the Ukraine crisis right now:

*Ukraine claims to have expelled Russian troops from its second city Kharkiv in the east of the country after Russian armored vehicles got through its defenses.

*Moscow says its forces have "entirely" besieged the southern Ukrainian city of Kherson and Berdyansk in the southeast on the Sea of Azov.

*Washington says the invading forces have lost "momentum over the last 24 hours" after meeting stiff resistance and still have not gained air superiority.

*The UN's refugee agency says at least 368,000 people are fleeing the fighting, with most crossing into Poland. Tens of thousands are also seeking shelter in Hungary, Romania, and Moldova.

*Germany's train operator Deutsche Bahn offers free rides to refugees traveling into the country from Poland.

*Pope Francis calls for the "urgent" opening of humanitarian corridors for civilians to flee the fighting.

*Ukrainian President Volodymyr Zelensky says he is ready to meet Russia for "honest talks" but not in Belarus as Moscow demands since the country is being used as a launchpad for attacks on Ukraine.

*Zelensky urges foreigners to sign up for an "international brigade" of volunteers at Ukrainian embassies to help fight to invade Russian forces.

*Germany says it is sending 1,000 anti-tank weapons and 500 "Stinger" surface-to-air missiles to help Ukraine, after the United States vows $350 million in additional military funding.

*France, Belgium, the Czech Republic, Portugal, and Greece are also rushing military equipment, light weapons or fuel there, while Italy gives 110 million euros in immediate aid.

*Western nations including Japan pledge to remove some Russian banks from the SWIFT interbank system, crippling part of its global trade.

*Former US President Donald Trump praises Russian leader Vladimir Putin as "smart", claiming "this horrific disaster would never have happened if our election was not rigged."

*Trump had earlier described Putin's invasion plan as a "genius" move.

*Germany will invest 100 billion euros ($112 billion) in military equipment this year and plough more than two percent of its economic output in defence annually after Russia's invasion of Ukraine, Chancellor Olaf Scholz says.

*Google follows Facebook in preventing Russian state media from earning money on its platforms in response to the invasion of Ukraine.

*The Czech Republic, Sweden, and Poland refuse to play Russia in the World Cup playoffs because of their invasion of Ukraine.

Elon Musk orders his SpaceX's Starlink satellite service to supply broadband to Ukraine after a government minister pleads for help after Russia blocked internet coverage.

* Western allies announced sweeping new sanctions against Moscow, as President Volodymyr Zelenskiy said Ukraine's forces were repelling Russian troops advancing on Kyiv.

* The SWIFT international payments system said it was preparing to implement steps by the West against some Russian banks, a move that will inflict a crippling economic blow to Moscow but also cause much pain to Western companies and banks.

* At least 198 Ukrainians, including three children, have been killed in Russia's invasion, the head of the Ukrainian Health Ministry was quoted by the Interfax news agency as saying.

* Russian forces blew up a natural gas pipeline in Ukraine's second city, Kharkiv, while Russian-backed separatists said Ukraine had blown up an oil terminal in the breakaway Luhansk province. Russia continues to supply Europe with gas via Ukraine.

* Refugees continued to pour across Ukraine's western borders, with around 100,000 reaching Poland in two days.

* Ukraine denied that it was refusing to negotiate a ceasefire with Russia but said it was not ready to accept ultimatums or unacceptable conditions.

* A Ukrainian road maintenance company said it was removing all road signs to hinder invading Russian forces: "Let us help them get straight to hell."

* In a sea of blue and yellow flags and banners, protesters around the world expressed support for the people of Ukraine and called on governments to do more to help Kyiv, punish Russia and avoid a broader conflict.

* Russian billionaire Roman Abramovich said he was given stewardship of Chelsea to the London soccer club's foundation.

"We will fight as long as it takes to liberate the country," Zelenskiy said in a video message.

- "We will hold Russia to account and collectively ensure that this war is a strategic failure for Putin," the leaders of the European Commission, France, Germany, Italy, Britain, Canada, and the United States wrote.

Russian forces have attacked oil and gas facilities in Ukraine, sparking huge explosions, officials said on Sunday, as Western allies prepared new sanctions, including banishing key Russian banks from the main global payments system.

Ukrainian forces were holding off Russian troops advancing on the capital, Kyiv, said President Volodymyr Zelenskiy as the biggest assault on a European state since World War Two entered its fourth day. Russian missiles found their mark, including a strike that set an oil terminal ablaze 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. There were also reports of heavy fighting near Ukraine's second city, Kharkiv, in the northeast, where Russian troops blew up a natural gas pipeline, a Ukrainian state agency said. The gas blast there sent a mushroom cloud up into the darkness.

The United States and its European partners said they also would impose restrictions on Russia's central bank to limit its ability to support the rouble and finance Putin's war effort.

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.

Google barred Russia's state-owned media outlet RT and other channels from receiving money for ads on their websites, apps and YouTube videos, similar to move Facebook made.

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, Interfax quoted Ukraine's health ministry as saying. Interfax later cited the regional administration in Donetsk, eastern Ukraine, saying 17 civilians had been killed and 73 wounded by Russian shelling.

"Italy has decided to close its airspace to Russia," Foreign Minister Luigi Di Maio said on Twitter, confirming earlier comments from a government spokesman.