WASHINGTON: The White House called for an immediate end Sunday to clashes between security forces and protesters in Ukraine, warning of possible sanctions.

Dozens of people were wounded during the bloody confrontations in the capital amid a nearly two-month standoff between the opposition and President Viktor Yanukovych.

“We are deeply concerned by the violence taking place today on the streets of Kiev and urge all sides to immediately de-escalate the situation,” National Security Council spokeswoman Caitlin Hayden said in a statement.

“The increasing tension in Ukraine is a direct consequence of the government failing to acknowledge the legitimate grievances of its people.”

The latest violence came as 200,000 people defied new restrictions on protests to rally against Yanukovych.

In near apocalyptic scenes close to parliament, several police buses and vehicles were torched by the protesters who hurled stones and Molotov cocktails at security forces. Police responded with tear gas and stun grenades.

Hayden said the Ukrainian government has “moved to weaken the foundations of Ukraine's democracy by criminalising peaceful protest and stripping civil society and political opponents of key democratic protections under the law.”

President Barack Obama's administration also renewed calls for the government to hold talks with the opposition.

“We urge the government of Ukraine to take steps that represent a better way forward for Ukraine, including repeal of the anti-democratic legislation signed into law in recent days, withdrawing the riot police from downtown Kiev and beginning a dialogue with the political opposition,” Hayden said.

“From its first days, the Maidan movement has been defined by a spirit of non-violence and we support today's call by opposition political leaders to reestablish that principle.”

The spokeswoman warned that “the US will continue to consider additional steps — including sanctions — in response to the use of violence.”