A senior rebel leader in eastern Ukraine has claimed the Minsk peace deal will fail unless Kiev recognises the independence of rebel-held territory.
Aleksandr Zakharchenko told the BBC he wanted to expand the self-proclaimed republic he leads in Donetsk.
He said the Minsk ceasefire agreement brokered by the West was not being properly implemented by the government.
“Ukraine doesn’t want to resolve all the issues,” he said.
“If you agree to resolve something, then you need to act and move forward, and resolve everything that’s included.
“If that doesn’t happen, then the Minsk Agreement is unfulfilled, and it renders all the meetings in Minsk pointless,” he added.
He also accused Kiev of preparing for war – a charge it denies.
“According to the information we’ve received, Kiev could once again provoke the conflict very soon, attacking Donetsk or any another town of the Donetsk People’s Republic.”
Under the Minsk agreement, backed by European leaders, Ukraine’s government claimed that the rebel-held east would remain part of the country.
But Mr Zakharchenko insisted it must be legally recognised as an independent territory.
He said: “Ukraine has stopped paying welfare, pensions and other payments that are obligatory for a state to pay its citizens.
“They don’t do it, so they’ve de facto recognised us.”
The BBC’s Tom Burridge reports that throughout this week shelling could be heard in central Donetsk, a sign that the Minsk deal had not brought real peace to the region.
Both sides were largely thought to have adhered to the ceasefire deal – until a recent escalation of fighting near Donetsk and Shyrokyne.
Ukraine and the rebels both claim to have withdrawn heavy weapons from the line of contact but both sides have accused each other of planning fresh offensives and strengthening military hardware.
On Friday, the UN Human Rights Commissioner said at least 6,116 people have been killed since the fighting broke out a year ago.