The government received 229 votes, three more than the minimum of 226 required for approval.
But, in an unexpected development, parliamentary Speaker Volodymyr Groysman said a second round of voting would be held later on Tuesday following a debate in the 450-seat assembly.
On another note, international monitors in eastern Ukraine said government troops and Russian-backed separatist forces in the Luhansk region have agreed on a new cease-fire.
The Organization for Security and Cooperation in Europe said in a statement late Monday that hostilities will cease Friday along the line of contact between the warring sides.
The OSCE said it was agreed at negotiations that took place Saturday that heavy weapons will start being withdrawn from the front at the weekend.
A similar deal was reached Monday to end fighting over the airport in the capital of the more heavily populated Donetsk region, but rocket barrages continued for hours in that area all the same.
A cease-fire was nominally agreed in early September, but hundreds have been killed since then amid daily violations of that truce.