Congo's main opposition bloc was not immediately available for comment, but has already called for a general strike.
Democratic Republic of Congo's ruling coalition and other smaller parties have agreed to delay next month's elections to April 2018 - a move that will anger opposition groups who have accused the president of trying to cling onto power.
Congo's main opposition bloc was not immediately available for comment, but has already called a general strike for Wednesday to press President Joseph Kabila to leave at the end of his mandate this year.
Past moves to delay the election have triggered violent demonstrations.
Parties agreed in talks on Saturday to keep Kabila in office until the vote, said one organisation in the discussions, the Union for the Congolese Nation.
But most other opposition groups boycotted the negotiations, saying they were a pretext for letting Kabila keep the top job.
UNC president Vital Kamerhe is widely expected to become prime minister as part of the power-sharing government ushered in under the talks.