KIEV/DONETSK, Ukraine, (Reuters) - Ukraine's government kept up military pressure against pro-Russian rebels on Tuesday, threatening them with an "nasty surprise", while the militants said they were preparing to fight back after losing their main stronghold.
President Petro Poroshenko, drawing confidence from the fall of the rebel bastion of Slaviansk at the weekend, named a new chief of military operations in the east following his appointment of an aggressive new defence minister who again demanded the separatists lay down their arms.