South African President Jacob Zuma (1st R) visits local communities of Mhlabuyalingana in northern KwaZulu-Natal Province of South Africa bordering Mozambique, on March 14, 2017.(Xinhua/DOC/Kopano Tlape)

CAPE TOWN, April 12 (Xinhua) -- South African President Jacob Zuma celebrated his 75th birthday on Wednesday with a pledge to win the fight against racism.

"We remain committed to building a non-racial society and will continue to work hard to unite our people against racism and all it's manifestations," Zuma said in his birthday message.

Zuma said one of his birthday wishes is to "see us winning the battle against racism in our country."

He said he would also like to see South Africans making more progress in fighting poverty and inequality.

"We need to make progress in black economic empowerment to promote true economic freedom," Zuma said.

He urged South Africans to work together to find solutions following the recent sovereign credit downgrades.

As Zuma celebrated his birthday, opposition parties and civic organizations organized marches in parts of the country, calling for Zuma to resign.

The marches were follow-ups of the nationwide anti-Zuma protests on April 7.

On Monday, Zuma said these protests were signs of a resurgence of racism.

Zuma said many placards and posters carried by the protesters "displayed beliefs that we thought had been buried in 1994."

Some posters depicted black people as baboons, Zuma said, stressing that "racists have become more emboldened" in the country.

There have been growing calls for Zuma to resign after he reshuffled the cabinet on March 31, sacking or replacing 10 ministers and 10 deputy ministers.

The reshuffle led international rating agencies Standard & Poor's and Fitch to downgrade South Africa's credit rating to junk status.

As part of his birthday celebrations, Zuma will join the ruling African National Congress (ANC) for a celebration rally on Wednesday afternoon in Soweto, southwest of Johannesburg.

Also on Wednesday, the ANC sent revolutionary well wishes to Zuma, also president of the ANC.

Zuma has committed his life and energies to the liberation of the people of South Africa, in particular, the oppressed and the poor of the poorest, the ANC said.

"We salute and are grateful to him, and many other freedom fighters, for their unmatched sacrifices in the struggle for a just course," the party said.

In more than 22 years since the end of apartheid in 1994, Zuma has continued to pursue the struggle for economic freedom, said the ANC.

"In particular, the president has been at the forefront of the efforts to build a National Democratic Society underpinned by radical socio-economic transformation characterized by inclusive growth and a better life for all our people," the ANC said.