Pro-Russian separatists
Armed pro-Russian separatists stand guard in Siversk, Ukraine. Reuters

Ukrainian President Petro Poroshenko on Friday announced a cease-fire in his government’s offensive against pro-Russia separatists in the eastern portion of the country.

"The forces of the anti-terrorist operation will halt military action starting today and through June 27," he said in a statement attributed to him by Ukraine’s interior ministry, the Associated Press reported. The one-week cease-fire, part of a plan to de-escalate tensions with the separatists, also includes a directive for pro-Russian fighters to leave Ukraine and new local elections in the east.

But Poroshenko said Ukraine will fight back if the separatists fire on his troops.

"Combat action will only be of retaliatory character if rebels attack our forces," he said.

The cease-fire announcement came the same day the speaker of Ukraine’s parliament said the military closed off Ukraine’s eastern border with Russia, according to CNN.

Since March, the government has been battling pro-Russia separatists who in some cases declared their territory independent from Ukraine. Kiev is also angered at Moscow’s annexation of Crimea, where residents voted in a March referendum that Ukraine, the U.S. and the EU said was illegal.