FF Plus leader Pieter Mulder is one of the members of the newly formed Collective for Democracy.
Five opposition parties have formed a coalition called the Collective for Democracy to contest the general elections next year, they announced on Tuesday.
The new party consists of the African Christian Democratic Party (ACDP), Congress of the People (Cope), the Freedom Front Plus (FF Plus), the Inkatha Freedom Party, and the United Christian Democratic Party.
"The political dynamics have now changed as the diversity of South Africa is now represented effectively in our Collective for Democracy," chairperson Mosiuoa Lekota, also leader of Cope, said.
"We now have an opportunity to bring voters the hope of actual political change instead of giving up on alternatives because the ruling party has cynically manoeuvred its way into all sectors of our society, entrenching its power and corruption."
The parties said they would work to advance democracy and contest the general election with a view to securing enough representation to form a new government.
Lekota said the Collective for Democracy had been negotiated over a number of years with a view to finding common ground.
The agreement centred on the "joint areas of priority", which consisted of 20 points that were negotiated and formally accepted at a signing ceremony on Tuesday.
The agreed areas included prioritising education and training, referring the Protection of State Information Bill to the Constitutional Court, ensuring strict separation of party and state, and the review of the "bloated" government to ensure efficiency and affordability.
"The Collective for Democracy will soon announce their team of potential representatives that will draw on the best people within the parties while focusing on corruption free, competent, trusted candidates," it said.
ACDP MP Cheryllyn Dudley of the ACDP said her party had embraced the CD.
"The ACDP has embraced and committed to the realisation of a shared future for all South Africans, and the CD is a demonstration of this commitment to a peaceful and prosperous SA for all who live here," she said.
FF Plus leader Pieter Mulder said: "Coalitions are an important part of our electoral system and makes it possible for voters to vote for the party closest to their values, but still vote against the ANC.
Our wonderful country is diverse, and so our future should reflect that." Other opposition parties were welcome to join the coalition, as long as they committed to the agreed principles, the CD said. – Sapa