The National Assembly is set to fight Cope leader Mosiuoa Lekota's court challenge against it, Parliament said on Friday.
Last week, Lekota served National Assembly speaker Max Sisulu and his deputy Nomaindia Mfeketo with court papers.
The Congress of the People leader is challenging his ousting from a National Assembly sitting.
He was asked to leave after he refused to apologise for accusing president Jacob Zuma of violating his oath of office by not protecting the rights of artist Brett Murray and City Press editor Ferial Haffajee.
Murray painted the now defaced artwork "The Spear". Haffajee removed a picture of the painting from the newspaper's website, after significant pressure from Zuma's allies.
Lekota wants the Mfeketo's ruling against him set aside. He is also seeking an order declaring the deputy speaker's ruling to be unlawful and inconsistent with the Constitution.
But both Mfeketo and Sisulu claim the ruling was justified.
"The Speaker and the Deputy Speaker will oppose the application on the basis that, in making her ruling, the Deputy Speaker acted within her Constitutional powers," Parliament said in a statement.
Last week, ANC chief whip Mathole Motshekga described Lekota's court challenge as a publicity stunt.
"It is a laughable and bizarre court action, which Lekota himself knows stands no chance of succeeding," Motshekga said.