(Reuters) – Russia enters the third month of its never-ending invasion of Ukraine on Sunday ahead of the fighting that has killed thousands, uprooted millions and reduced cities to rubble.

Faced with mounting sanctions and fierce Ukrainian resistance reinforced by Western weapons, Russia continued its long-range bombardments and opened a new offensive in the east.

* February 24: Russia invades Ukraine on three fronts in the biggest assault on a European state since World War II. Tens of thousands flee.

* Russian President Vladimir Putin announces he is launching a “special military operation” to demilitarize and “denazify” Ukraine. Ukrainian President Volodymyr Zelenskiy tweets: “Russia has gone down the wrong path, but Ukraine is fighting back.”

* February 25: Ukrainian forces fight the Russian invaders to the north, east and south. Artillery pounded kyiv and its suburbs and the authorities asked the inhabitants to prepare Molotov cocktails to defend the capital.

* February 26: A US defense official says Ukrainian forces are putting up “determined resistance”.

* February 28: Initial talks between the two sides fail to make any breakthrough.

* March 1: Russia strikes a TV tower in kyiv and steps up bombardment of northeastern Kharkiv and other cities, in what is seen as a change in tactics as Moscow hopes of a charge fast on the capital fade.

* A US official said a mile-long Russian armored column heading for kyiv had made no progress in the past 24 hours, bogged down by logistical problems.

* March 2: Russian forces shell the southern port of Mariupol for 14 hours and prevent civilians from leaving, says its mayor – the start of Moscow’s blockade of the city. Russia denies targeting civilians.

* Russian troops reach the center of the Black Sea port of Kherson and claim their first capture of a major urban center.

* March 3: Russia and Ukraine agree to set up humanitarian corridors for fleeing civilians. A cargo ship sinks near a Ukrainian port hours after another was hit by an explosion at another port.

* One million people have fled Ukraine, according to the UN refugee agency (UNHCR).

* March 4: Russian forces seize the nuclear power station of Zaporizhzhia, the largest in Europe. NATO rejects Ukraine’s call for no-fly zones, saying it would escalate the conflict. * March 6: “Rivers of blood and tears are flowing in Ukraine”, declares Pope Francis to the crowds in Saint Peter’s Square. “It is not just a military operation, but a war, which sows death, destruction and misery.”

* March 8: Civilians flee the besieged city of Sumy in the first successful humanitarian corridor. Two million people have now fled Ukraine, according to the UNHCR. * March 9: Ukraine accuses Russia of bombing a maternity hospital in Mariupol, burying people under the rubble. Russia later said the hospital was no longer functioning and had been occupied by Ukrainian fighters.

* March 13: Russia expands its war deep into western Ukraine, firing missiles at a base in Yavoriv near the border with NATO member Poland. The attack left 35 dead and 134 injured, according to a local official. * March 14: Russian journalist Marina Ovsyannikova bursts into a state television studio during a live news bulletin, with a banner reading: ‘NO WAR. Stop the war. Don’t believe the propaganda. They lie to you here.”

* March 16: Ukraine accuses Russia of having bombed a theater in Mariupol where hundreds of civilians are sheltering. Moscow denies it.

* March 25: Moscow signals it is scaling back ambitions and will focus on territory claimed by Russian-backed separatists in the east, as Ukrainian forces go on the offensive to retake towns outside kyiv.

* March 29: Ukraine proposes to adopt a neutral status during the talks in Istanbul.

* March 30: More than 4 million people have fled Ukraine, according to UNHCR.

* April 1: Ukraine reclaims more territory around kyiv from Russian soldiers who leave destroyed villages and abandoned tanks as they move away from the capital.

* April 3/4: Ukraine accuses Russia of war crimes after a mass grave and bodies of people shot at close range are found in the recaptured town of Bucha. The Kremlin denies responsibility and says images of bodies were staged.

* April 8: Ukraine and its allies accuse Russia of a missile attack on a train station in Kramatorsk that killed at least 52 people trying to flee the impending offensive from the east. Russia denies any responsibility.

* April 14: Russia’s main Black Sea warship, the Moskva, sinks after an explosion and fire that Ukraine says was caused by a missile strike. Russia claims the ship sank after an ammunition explosion. Washington believes the warship was hit by two Ukrainian missiles. * April 18: Russia launches its assault on eastern Ukraine, unleashing thousands of troops in what Ukraine has described as the Battle of Donbass, a campaign to seize two provinces and save a victory on the battlefield. * April 20: More than 5 million people have fled Ukraine, according to UNHCR.

* April 21: Putin declares the southeastern port of Mariupol ‘liberated’ after nearly two months of siege, despite leaving hundreds of defenders to hold inside a giant steelworks.

* April 22: Russian general says Moscow wants to take full control of southern and eastern Ukraine.

(Compiled by Andrew Heavens; Editing by Gareth Jones)

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