The Congress of the People is set to rise from the political ashes, its acting deputy president Smuts Ngonyama said on Monday.
"Cope will now rise... like a phoenix... and move up to higher levels once more," he told reporters in Cape Town.
At his side was Mluleki George, one of Cope's founders in 2008.
George - together with current leader Mosiuoa Lekota and Mbhazima Shilowa - quit the ANC to establish the new party, which went on to garner 7.42 percent of the vote in the 2009 election.
In the years that followed, Cope was riven by a leadership tussle between Lekota and Shilowa. The latter was subsequently sacked from the party, though continues to pursue the matter through the courts.
George, who was previously also at odds with the party, told reporters it was now time "to take one step back in order to take a jump forward".
Cope needed to prepare "to contest the general election in 2014". He believed the party still had an important role to play on the South African political scene.
"We are making a call to all Cope members, including those who were suspended and expelled, to join this genuine effort for unity and unification of all structures of the party," George said.
He was welcomed by Ngonyama, who said the day marked a "milestone" in the history of Cope.
Asked whether the party had lost members as a result of its years-long infighting, Ngonyama admitted that it had lost some, mainly back to the ANC.
"We did lose some numbers, but not a big number of people," he said.
He announced plans for the party's leadership to complete a tour of the provinces "to mobilise Cope supporters" ahead of an "all-inclusive" party congress later this year.
"We call on everybody to renew their membership and be ready for the establishment of constitutional structures at all levels this year," Ngonyama said.
Lekota was not present at Monday's briefing.
Ngonyama said he was in Johannesburg dealing with legal issues around Shilowa's court bid.