A senior leader of pro-Russian rebels in eastern Ukraine has claimed in an interview that the fragile Minsk peace agreement will collapse unless Kiev recognizes a self-proclaimed rebel state.

Aleksandr Zakharchenko, the president of the Donetsk People's Republic, told the BBC: “Ukraine doesn't want to resolve all the issues. … If that doesn't happen, then the Minsk Agreement is unfulfilled, and it renders all the meetings in Minsk pointless."

He also claimed that Kiev had effectively already recognized the self-proclaimed state that he leads, the legitimacy of which has been widely rejected by the international community.

“Ukraine has stopped paying welfare, pensions and other payments that are obligatory for a state to pay its citizens,” he said.

"They don't do it, so they've de facto recognized us," he added.

Zakharchenko has been increasingly bellicose towards Ukraine in recent days. Earlier this week, he threatened that pro-Russian rebels would take the city of Mariupol, if Ukrainian forces continued their “aggression” toward them.

The claims of aggression on the part of Ukrainian forces are nothing new. Zakharchenko told Bloomberg this week that the chances of full-scale war are now “very high, 90 percent.”

“The enemy is actively preparing for offensive actions, enforcing front line positions,” he added.

The Minsk II peace accord, which came into force in mid-February, appears to be in peril at present, as fighting and explosions have been reported in contested areas, and government forces lost six soldiers in a single day, making it the deadliest day in almost two months.

Ukraine and many Western governments accuse Russia of supporting the rebels with military equipment and troops, a claim that Russia denies.