Four Ukrainian soldiers have been killed and 10 others wounded in unrest in the east during the past 24 hours, security officials in Kiev said Saturday.
One civilian, a 60-year-old man, was also killed in the eastern region of Lugansk on Friday, the governor's office announced.
Ukrainian forces are locked in a struggle with pro-Moscow separatists for territory in eastern Ukraine.
A ceasefire has been in place since early September but this has not stopped almost 1,000 people from dying in fighting since, according to the United Nations.
Ukraine's new coalition government declared joining NATO a priority on Friday in a move likely to provoke fresh anger from Russia, which denies supporting the rebels.
Ukraine's military on Friday also accused Russia of shelling its territory for the first time since the ceasefire was signed.