By Stella Mapenzauswa

JOHANNESBURG (Reuters) - A senior member of South Africa's ruling ANC urged its top leaders including President Jacob Zuma to quit on Sunday, saying fraud charges against Finance Minister Pravin Gordhan reflected an abuse of power to settle political scores within the party.

ANC parliamentary chief whip Jackson Mthembu's comments come a week after Deputy President Cyril Ramaphosa publicly expressed support for Gordhan, saying the case against him should not be allowed to undermine his efforts to revive the economy.

Prosecutors have ordered Gordhan to appear in court on Nov. 2, in what his supporters and analysts say is an attempt to muzzle the Treasury over its criticism of the undue political influence exerted by a wealthy family close to Zuma.

"In my view, a minister is being pursued for political reasons, and then charged with fraud. That's why I've then said, perhaps we are not the leadership that can take the ANC forward under these conditions," Mthembu said on ENCA television.

"President Jacob Zuma is the president of the ANC. When I said the entire ANC leadership that has already taken collective responsibility must take the fall, I meant everybody, myself included, including President Zuma," he said.

South African media has reported growing rifts within the African National Congress since the liberation movement of Nelson Mandela, which has been in power since 1994, suffered its worst electoral performance in August.

Unemployment, economic stagnation and scandals around Zuma led voters to punish the ANC in the local government vote, changing the outlook for national elections in 2019.

Publicly, Gordhan has said that he still enjoys a good relationship with Zuma, and that he is hard at work preparing a budget policy speech to be delivered next week.

But investors fear his prosecution on charges of committing fraud while running the tax agency could see Gordhan removed as finance minister, opening South Africa to possibly losing its investment grade credit rating.

Business leaders and rights groups have also voiced their support for Gordhan, and on Sunday the think-tanks Freedom Under Law and the Helen Suzman Foundation said they had filed an urgent court application to have the charges against him set aside.

"The application by FUL and the HSF does not seek to protect particular individuals, or to take any side in factional battles," they said in a statement.

"It is about protecting the machinery of the state from being undermined for malign purposes, thereby also preventing further damage to our fragile economy at a sensitive time."

(Editing by Toby Chopra)