The main opposition party of the Democratic Republic of Congo (DRC) has strongly rejected a decision to push back this year's election to April 2018, calling it a "flagrant violation" of the constitution.
The postponement of the vote, which hands President Joseph Kabila more than a year of extra time in office, was approved by the country's constitutional court on Monday following talks between the ruling coalition and smaller parties.
Most opposition forces, however, boycotted the "national dialogue" and called for a nationwide general strike on Wednesday to put pressure on Kabila.
WATCH: DR Congo and the General
The Union for Democracy and Social Progress (UDPS), which is led by veteran opposition leader Etienne Tshisekedi, strongly rejected the postponement plan, the party's secretary-general Jean-Marc Kabund told AFP news agency on Tuesday.
Kabund said the move "unilaterally imposes Mr Kabila in flagrant violation of the constitution which sets the end of his mandate at December 20".
Should the agreement now hold, a new government would be set up, with the key post of prime minister handed to an opposition figure.
Al Jazeera's Catherine Soi, reporting from the capital Kinsasha, said that voter registration is now expected to begin in July.
Our correspondent said that the electoral commission had previously indicated that it was "logistically impossible" to hold the election this year because of "security challenges".
Kabila is banned under the constitution from running for a third term.
Last month, dozens of people died in Kinshasa as security forces clashed with anti-government protesters calling for the president to leave office when his mandate runs out in December.
Earlier on Tuesday, French Foreign Minister Jean-Marc Ayrault said the postponement plan was "no response to the crisis", and called Kabila to announce that he will not run for office.
The European Union has threatened sanctions if the country does not hold elections in 2017.
Kabila, who came to power in 2001 when his father was assassinated, says he will respect the constitution but has not made clear if he plans to find a way to run again.
