Ukraine's President Petro Poroshenko has raised hopes that a deal could be struck with Russia to end fighting in the east of his country.
Ukraine, Russia and pro-Russia rebels are set to begin afternoon talks in Belarus. However, there are new reports of shelling near the town of Mariupol.
Meanwhile, Western countries are preparing to tighten sanctions on Russia in case talks come to nothing.
They are attending the second day of a Nato summit in Newport, Wales.
The West accuses Russia of sending arms and troops to back the rebels in eastern Ukraine. Moscow denies this.
More than 2,600 people have died during the five-month conflict.
Leaders will also discuss the growing threat of Islamic State (IS) in Iraq and Syria.
An IS video released on Tuesday showed the killing of US journalist Steven Sotloff, just days after the group beheaded another American reporter, James Foley.
In the latest video, an IS militant is seen threatening to kill a UK hostage, aid worker David Haines, who was seized in March 2013 in Syria's Idlib province.
Nato Secretary General Anders Fogh Rasmussen said Nato had pledged "seriously" to examine any plea by Iraq to fight IS militants.
UK Prime Minister David Cameron said that his country was deciding whether to arm the Kurds.
Also on the agenda is the situation in Afghanistan, where the alliance is due to end its combat operations at the end of this year.
However, there is no government in place in Kabul to complete the handover because the outcome of presidential elections earlier this year is still being contested.
Taliban militants launched a deadly attack on a government compound on Thursday.
Source: BBC