A Democratic Republic of Congo official says the presidential poll scheduled for 2016 could be delayed a year.
Government spokesman Lambert Mende told Radio France International on Friday that the election "could take place in 2016 or it could take place in 2017."
Opposition parties have accused President Joseph Kabila of trying to extend his term through a proposed law that would require completion of a national census before elections are held.
The bill won preliminary approval in parliament this week, but opposition leaders have called for protesters to occupy the parliament building on Monday to block final passage.
Any national census in Congo would be complicated by a lack of paved roads and chronic unrest in several eastern provinces.
Kabila is currently serving a second elected five-year term. The constitution blocks him from running for a third time.
Material for this report came from AFP and Reuters.