Number of refugees fleeing Ukraine reaches 1.5 million

The latest:

More than 1.5 million refugees from Ukraine have crossed into neighbouring countries in the space of 10 days, the fastest growing refugee crisis in Europe since the Second World War, UN High Commissioner for Refugees Filippo Grandi said on Sunday.

That number was announced as Kyiv pressed the West to toughen sanctions and deliver more weapons to repel Russia's attack, now in its 11th day.

Ukrainian police said there was relentless Russian shelling and air raids in the northeast Kharkiv region, reporting many  casualties, while the UN World Health Organization said there had been several attacks on Ukrainian health-care facilities.

Moscow and Kyiv have traded blame over Saturday's failed ceasefire to allow civilians to flee Mariupol and Volnovakha,  two southern cities besieged by Russian forces. Ukraine said more talks were set for Monday, but Russia was less definitive.

People who have been able to escape Ukraine spilled into neighbouring Poland, Romania, Hungary and Slovakia.

U.S. Secretary of State Antony Blinken was in Moldova on Sunday, pledging America's support to the small Western-leaning former Soviet republic, which is also coping with an influx of refugees from neighbouring Ukraine.

Elsewhere, Ukrainian President Volodymyr Zelensky called on those in areas occupied by Russian troops to fight.

"We must go outside and drive this evil out of our cities," he said in an address on Saturday night.

On Sunday, he again called on foreign countries to impose a no-fly zone over Ukraine, saying in a video address that "the world is strong enough to close our skies."

NATO countries have ruled out policing a no-fly zone, which would bar all unauthorized aircraft from flying over Ukraine. Russian President Vladimir Putin said Saturday that Moscow would consider any third-party declaration of a no-fly zone over Ukraine as "participation in the armed conflict."

British military intelligence said on Sunday that Russian forces were targeting populated areas in Ukraine, comparing the tactics to those Russia used in Chechnya in 1999 and Syria in 2016. But it said Ukrainian resistance was slowing the advance.

"The scale and strength of Ukrainian resistance continue to surprise Russia," British military intelligence said.

Russia has repeatedly denied targeting civilian areas.