Thousands of demonstrators on Sunday took to the streets in cities across Europe for the second weekend running to protest against Russia's invasion of Ukraine.

Moscow's assault on its pro-Western neighbour on February 24 has sparked global condemnation and an outpouring of solidarity with Kyiv as the West inflicts harsh sanctions, some directed against Russian President Vladimir Putin himself.

In Brussels, police said around 5,000 people took part in a rally marked by a sea of Ukrainian flags
In Brussels, police said around 5,000 people took part in a rally marked by a sea of Ukrainian flags BELGA via AFP / NICOLAS MAETERLINCK

Rallies were again organised across the continent following demonstrations on Saturday to denounce Russia's actions and demand an end to the conflict.

In Brussels, police said around 5,000 people took part in a rally marked by a sea of Ukrainian flags and chants of "Russians, go home!", "No to war" and "Europe, be brave, act now!".

Protesters in Toulouse -- which is twinned with Ukraine's capital Kyiv -- assembled behind a large banner
Protesters in Toulouse -- which is twinned with Ukraine's capital Kyiv -- assembled behind a large banner AFP / Lionel BONAVENTURE

Protesters in the French city of Toulouse -- which is twinned with Ukraine's capital Kyiv -- assembled behind a large yellow and blue banner, holding portraits showing a bloodstained Putin and labelling him an assassin.

Cries of "close the airspace" and "Let's protect Ukraine's sky" resounded through the city, a reference to Kyiv's demand that NATO establish a no-fly zone to prevent Russian aircraft contributing to Moscow's onslaught.

Around 5,000 people also gathered in the northern city of Caen by a memorial commemorating the 1944 D-Day landings, a key turning point in the battle against Nazi Germany in World War II.

Moscow's assault on Ukraine has sparked global condemnation and an outpouring of solidarity for Kyiv
Moscow's assault on Ukraine has sparked global condemnation and an outpouring of solidarity for Kyiv AFP / JUSTIN TALLIS

The Ukrainian flag was hoisted and many attendees sported the yellow and blue colours of the Ukrainian flag, an AFP correspondent saw.

"People of Ukraine, we won't desert you! Democracy, freedom, peace," read one placard.

In Spain, protests unfolded in the capital Madrid, Barcelona and other cities across the country
In Spain, protests unfolded in the capital Madrid, Barcelona and other cities across the country AFP / LLUIS GENE

In Spain, protests unfolded in the capital Madrid, Barcelona and other cities across the country.

Rallies were again organised across Europe following demonstrations to denounce Russia's actions and demand an end to the conflict
Rallies were again organised across Europe following demonstrations to denounce Russia's actions and demand an end to the conflict AFP / Robert ATANASOVSKI

Authorities said about 800 people congregated in Barcelona's central square with banners saying "Close the sky, not your eyes", "NATO, protect Ukraine's sky" and "Stop Putin, stop the war".

"They are attacking, destroying and killing civilians for no reason," Ukrainian Natalia Brodovska, who has lived in Spain for eight years, told AFP.

"It's horrible, we can't sleep or eat. I think all Ukrainians feel that. But the situation of my people who are in Ukraine is a lot worse," the 45-year-old lawyer said.

Thousands of Russians defied the authorities and around 2,500 were detained on Sunday for protesting against the war.

A police spokeswoman said 1,700 people were arrested in Moscow after around 2,500 took part in an "unsanctioned protest", while 750 were detained at a smaller rally of around 1,500 people in the second-largest city, Saint Petersburg, Russian news agencies reported.

OVD-Info, which monitors detentions at opposition protests, put the figure of detainees in 49 towns and cities across Russia at 2,575 people and said police used electric shockers on protesters.

The latest detentions brought the total number of demonstrators held to more than 10,000 since the invasion began.

In Serbia's capital Belgrade -- where a pro-Putin protest in support of Russia's invasion took place two days before -- hundreds of demonstrators gathered to express their solidarity with Ukraine.

"We want to save Belgrade's face because what happened on Friday (the pro-Russian protest) is absolutely shameful," Zdravko Jankovic, a 46-year-old mathematician, told AFP.

Around 100 people came out in support of Ukraine in Skopje, the capital of North Macedonia.

Gatherings were also reported in Britain, Germany, Bulgaria and Montenegro on Sunday.

Thousands of protesters descended on the streets of cities across the world, including in Paris, New York, Rome and Zurich, on Saturday to demand an end to the conflict.