There has been no official confirmation from the opposition, the EU or Russia that a deal has been reached.
KIEV, Ukraine — A tentative deal that promises early elections has been reached in a fresh bid to resolve Ukraine's political crisis following all-night talks with leaders from the opposition and representatives from the European Union and Russia, the Ukrainian president's office said Friday.
A brief statement released on the website of President Yanukovych's office on Friday morning said a formal agreement will be signed later in the day. The statement gave no further details.
An additional statement by Yanukovych said he would start the process for early elections but gave no date.
He also promised constitutional reforms trimming presidential powers, a key demand of protesters.
"As the president of Ukraine and the guarantor of the Constitution, today I am fulfilling my duty before the people, before Ukraine and before God in the name of saving the nation, in the name of preserving people's lives, in the name of peace and calm of our land," the president said in a statement on his website.
But crucially, there has been no official confirmation from the opposition, the EU or Russia that a deal has been reached and there are reports of continuing violence on the streets of Kiev.
French Foreign Minister Laurent Fabius, who was involved in the talks along with his German and Polish counterparts, said on Europe-1 radio Friday that "as long as things are not effectively completed, we must remain very prudent."
"The opposition wants to consult a certain number of its supporters, which is understandable," he said. "We discussed all subjects during these negotiations. It was done in an extremely difficult atmosphere, because there were dozens of dead and the country is on the verge of civil war."
A lull in fighting appeared to hold on Friday morning, as several thousand protesters milled around Maidan Square, and volunteers walked freely to the protest camps to donate food and other packages.
Looking exhausted, the protesters expressed defiance.
"We are strong because we are together," said Stepan Kubiv, a protestor in the capita. "On Wednesday, the fascists declared a truce. "Yesterday morning, I met a friend here — now he is dead."
"We are one, and we will never break Ukraine apart. Kiev stands."
In a sign of the high tensions, armed law enforcement officers tried to enter parliament Friday morning during a debate over measures to end the crisis. Shouting lawmakers pushed them out.
On Thursday, leaders in Europe voted to impose sanctions on Ukraine's leaders after a truce was shattered by government police who fired into crowds of protesters, killing as many as 100 people in the bloodiest day of violence since the confrontation began in November.
What began as a movement to force the government to sign a trade deal with the European Union is now one calling for the government to step down and new elections.
Hjelmgaard reported from London; the Associated Press contributed