Leaders in Minsk have agreed on a ceasefire in eastern Ukraine after around 17 hours of marathon talks. Read the latest here.
All times given in Central European Time.
11:48 : Ukraine, Russia, Germany and France have discussed setting up a monitoring body to oversee the enforcement of the ceasfire agreement in eastern Ukraine. "The heads of state and government feel bound to the execution of the agreements in Minsk. To this end, they agree upon the creation of a monitoring mechanism in the Normandy format, which will come together at a regular basis at the level of senior foreign ministry officials," the leaders said in a common statement.
11:34 : Russian President Vladimir Putin put pressure on Ukraine's separatists to agree on the ceasefire, German Chancellor Merkel has said.
11:33 : The Ukraine deal has given "hope for a peaceful resolution" of the conflict, rebel leaders said. "We cannot but give Ukraine this chance, the whole country will change," rebel leader Igor Plotnitsky told AFP after signing the deal.
11:25 : French President Francois Hollande has expressed his satisfaction with the Ukraine ceasefire agreement. "This is a relief for Europe and a fine example of what France and Germany can do for peace," he said.
"The text, which has been signed by the contact group and the separatists, deals with all questions," Hollande told the press, adding that the document included decentralization, border control and the withdrawal of heavy artillery.
11:19 : German Chancellor Angela Merkel has said there is a "glimmer of hope" for Ukraine, but that a lot of work needs to be done.
11:05 : The European Union summit in Brussels, scheduled for Thursday, has been delayed because of the extended Ukraine peace talks in Minsk in Belarus. The summit is expected to begin around 1500 hours, two hours later than planned, EU President Donald Tusk's spokesman said.
11:00 : Germany's Foreign Minister Frank Walter Steinmeier summed up the talks, saying the deal was definitely not a breakthrough:
But there was hope. "We have, for the first time, clear time limits for the execution of the Minsk obligations - on elections, on border checks, on the exchange of prisoners, to name a few," he said.
10:53 : Ukranian President Petro Poroshenko spoke to journalists about the deal. "The main thing which has been achieved is that from Saturday into Sunday, there should be declared, without any conditions at all, a general ceasefire," he says.
10:48 : "After 17 hours, negotiations in Minsk have finished: ceasefire from February 15 at 00 hours, then withdrawal of weapons, therein lies hope," German Chancellor Angela Merkel's spokesperson Steffen Seibert has tweeted.
10:44 : Pro-Russian separatists have signed the peace deal, Hollande tells journalists, adding that German Chancellor Angela Merkel, Ukrainian President Petro Poroshenko and he himself would ask the European Union to support the deal at the EU summit later on Thursday.
10:37 : "All matters are dealt with by this document signed by the contract group and the separatists," Hollande tells journalists, referring to the ceasefire agreement.
10:32 : French President Francois Hollande has said there is still much work to be done, but this is a real chance to improve the situation.
10:22 : Leaders have reached an agreement on a division line for withdrawing heavy artillery from eastern Ukraine, Putin tells journalists in the Belarusian capital, Minsk.
10:13 : Russian President Vladimir Putin has announced a ceasefire in eastern Ukraine beginning midnight, February 15. "We have agreed on a ceasefire... We have agreed upon the basic points," Putin tells reporters.
09:31 : Ukraine is not satisfied with a Russian proposal on the demarcation line which separates rebels and Ukrainian forces and its position on the future status of rebel-held territory in eastern Ukraine, Russian news agency RIA has reported.
09:24: Pro-Russian separatists demand Ukraine's troops withdraw from Debaltseve, a strategic railway hub in the country's east, Reuters has reported.
09:20 : The International Monetary Fund (IMF) and Ukraine's government have reached a new financial deal worth $17.5 billion to rescue Kyiv's economy, IMF chief Christine Lagarde has told reporters in Brussels.
09:04 : Separatist leaders Alexander Zakharchenko and Igor Plotnitsky have refused to sign a ceasefire agreement following talks with the contact group in Minsk.
09:00 : Leaders of Germany, France, Russia and Ukraine are back in the negotiating room in Minsk.
08:29 : Russia is imposing "unacceptable" conditions and there is "no good news yet," Ukraine's President Poroshenko says, according to news agency AFP.
07:59 : German Chancellor Merkel and French President Francois Hollande plan to hold a short meeting after talks with Putin and Poroshenko, Russia's international news agency RIA reports.
07:48 : Separatist leaders Alexander Zakharchenko and Igor Plotnitsky have also joined the talks with the contact group.
07:38 : Negotiating parties want to enforce a ceasefire in Ukraine within the next 48 hours. New incidents of fighting have been reported from the war-torn areas in eastern Ukraine's Donbass area.
Strategic analyst on Russian affairs Yury Barmin tweets:
07:10 : Leaders in Minsk are close to a breakthrough. The 12-hour-long peace talks marathon has resulted in a document, which will be signed by the contact group - of German, French, Russian and Ukrainian representatives - and the rebel leaders. The document will demand the "concrete execution" of the peace plan outlined in the September 2014 ceasefire agreement.
06:54 : There is "hope" that an agreement will be reached in Minsk, a diplomatic source says.
06:40 : Leaders to sign Ukraine document, dpa reports.
German Chancellor Angela Merkel, French President Francois Hollande, Russia's Vladimir Putin, Ukraine's President Petro Poroshenko and rebel leaders from eastern Ukraine are still negotiating a ceasefire in Ukraine after peace talks, which began on Wednesday, dragged on into Thursday morning.
The German Foreign Ministry said the talks were "not easy and continuing," and that Foreign Minister Frank Walter Steinmeier would stay on until a deal was reached.
"I think we still have 5-6 hours of work to do," Poroshenko's deputy chief of staff Valeriy Chaliy wrote on Facebook.
Poroshenko was also scheduled to speak briefly at the European Union Summit in Brussels and update EU leaders on the Minsk talks.
The talks in Belarus' capital, Minsk, are aimed to end the conflict in eastern Ukraine in which more than 5400 people have been killed since it began last April.