Celebrities including Miley Cyrus and Arnold Schwarzenegger have voiced their heartache and horror following the Russian invasion of Ukraine.

Singer Cyrus, 29, took to Instagram Stories where she shared her experiences working in Ukraine, where she filmed the music video for her Mark Ronson collaboration, Nothing Breaks Like a Heart.

“This morning was heartbreaking waking up to the news that Ukraine had been invaded,” her post began.

“I had the most incredible experience filming Nothing Breaks Like a Heart in Kyiv, and I will be forever grateful to the local community who welcomed me with open arms.”

She added there have been reports that, “at least 40 local Ukrainians have been killed already, and this conflict can lead to many more deaths, another refugee crisis with so many forced to flee their homes and more.

“I am standing in solidarity with everyone in Ukraine who is affected by this attack and with our global community who is calling for an immediate end to this violence,’ the former Hannah Montana star concluded.

Former California governor and European native Arnold Schwarzenegger, 74, also took to the social media platform, writing: “My thoughts are with the Ukrainian people.

“I have been asked to do several interviews, but I believe the news should continue to focus on what’s happening on the ground - on the tragedy that has broken our hearts and on the courage of the Ukrainian people that has inspired us,” the Terminator star continued.

“I am not a foreign policy expert, so I will leave the analysis to smarter people than me. I do know what it’s like to grow up after a war, in an occupied country, and I know that in war and its aftermath, no one wins. Everyone suffers.

“War has a way of breaking the winners along with the losers. I have Ukrainian friends and fans and I have Russian friends and fans. As far as I can tell, none of them want this. I hope sanity will eventually prevail and end this unnecessary war before too many lives are broken,” he continued.

“In the meantime, I stand with the people of Ukraine. I share your grief and your hope for peace. You inspire me with your bravery and your humanity in the face of this nightmare. God bless you.”

Arnold also shared an ESPN story about former boxers Vitali Klitschko (who is now the mayor of Kyiv) and his brother Wladimir Kitschko, who have stated they will fight for Ukraine.

“Vitali and Wladimir @Klitschko, I am thinking of you, my friends. You were my heroes in the ring and you’re my heroes now,” Schwarzenegger tweeted.

Veteran Hollywood star Michael Douglas, 77, shared an Instagram post from the United Nations stating: “The children of Ukraine need peace, desperately, now.”

Brit actress Kate Beckinsale, 48, shared a post that revealed more than 40 Ukrainian soldiers and at least 10 civilians have already been killed by Russian forces.

While Russian model Irina Shayk, 36, simply shared an image with the peace sign over the entire world, along with three prayer hands emojis.

Actor and singer Jared Leto tweeted: “I’m hopeful that peace will prevail and nonviolent solutions will ultimately be found.”

In a follow-up tweet, the Dallas Buyers Club star added: “To my friends and family in Ukraine - my heart breaks that this conflict has escalated in such a devastating way. Please take great care and be as safe as you can. Sending thoughts to you and your loved ones during this chaotic and disruptive time.”

Also joining the online outpouring, singer Ariana Grande, 28, shared a post from Rescue.org, which read: “We stand with the people and families whose lives will be affected from the Russian attack on Ukraine.”