Nicola Sturgeon has said that the world “must stand in solidarity” with the people of Ukraine.
The First Minister insisted that Russia must face the “severest consequences” after Vladimir Putin launched military action against the nation.
Prime Minister Boris Johnson led a crisis meeting of senior ministers on Thursday morning and pledged that the UK and its allies will “respond decisively”.
He is due to address the nation on Ukraine and make a statement to Parliament on Thursday afternoon.
An initial package of sanctions against Russia were outlined by Johnson earlier this week.
But, there are now calls to go further in light of the escalation by Russia in the region.
On Twitter, Sturgeon condemned Russia and Putin for the “unprovoked aggression”.
“Overnight developments in Ukraine – however anticipated – are appalling and horrific,” she wrote.
“The Kremlin must face the severest consequences for this unprovoked aggression.
“And the world must stand in solidarity with the people of Ukraine.”
Scottish Labour leader Anas Sarwar also insisted that the aggression of Putin “cannot go unpunished”.
He said: “Today my thoughts and solidarity are with the people of Ukraine. They now face the unimaginable horrors of war.
“But human lives cannot be traded for Russia’s imperial ambition. Vladimir Putin’s aggression cannot go unpunished.”
Scottish Liberal Democrat leader Alex Cole-Hamilton warned of the impact that Putin’s actions will have.
“Putin has committed an unforgivable act of expansionist aggression. A needless loss of human life will now follow,” he said.
“His actions will destabilise peace both in Europe and around the World.”