In their birthday messages to Nelson Mandela - who celebrated his 94th birthday yesterday - the two struggle veterans said South Africa's leaders and the ANC had forgotten the former president's legacy and the party's role in improving people's lives .

Madikizela-Mandela - who in a letter last week accused the ANC of subjecting the Mandela family to "shabby treatment", and of abusing the Mandela name - said yesterday: "Our country is in deep trouble as we make promises and the promises are not fulfilled."

Speaking at the opening of an additional building at an orphanage in Ngqeleni, in Eastern Cape, Madikizela-Mandela warned the ANC of the effects its failures had on those who voted the party into power.

"These children are lucky that we [the Mandela family] made promises and these promises have been fulfilled. We see our people today in the streets demonstrating against us. It's one of the most painful things to observe that, 18 years down the line, we still have people who say we have failed them."

Madikizela-Mandela said it was "tragic" that Mandela was celebrating his birthday during a period of instability in the ANC.

Warning that the party was in "deep trouble", she told the SABC: "We cannot pretend all is well in the ANC.

"According to the secretary-general of the ANC, [Gwede] Mantashe, the ANC is imploding, and that is not the ANC that he [Mandela] gave his life for and that is not the ANC we all wanted it to be - especially on his birthday."

She said the country's leaders should not forget the meaning behind Mandela's birthday celebrations because his legacy was everlasting and intended to improve people's lives.

Tutu, speaking in Bloemfontein, had harsher words for the ANC.

Referring to the Limpopo textbook scandal, Tutu said the situation of pupils without books in the third term of the school year, and classes under trees, was unacceptable and betrayed what Mandela had fought for.

Tutu - who has over the years been critical of the government for failing the poor and vulnerable - said he was certain Mandela was not entirely aware of the state of education in South Africa.

"If he knew what was happening he would be crying ... it's totally unacceptable."

Tutu said there was no justification for problems such as people living in shacks still plaguing the country.

"We hoped to inspire them to do things we hoped would characterise the new South Africa.

"That we have people going to bed hungry is unacceptable," Tutu told students at a global leadership summit meeting.

He criticised the  30% matric pass requirement.

"This is why we still struggle, maybe," he said, adding that people did not go to jail and die for such results.

Adding to Tutu's and Madikizela-Mandela's warning about the ANC's blunders, Cosatu general secretary Zwelinzima Vavi urged the ruling party to get its house in order or risk losing black support to the opposition DA.

"We are not in good standing; we are not in a good space," he said in Pretoria yesterday.

Judging by the growing black support for the DA, Vavi said, the party's leader, Helen Zille, was luring the most marginalised section of the country's population in an attempt to wrestle power from the ANC in the 2019 general elections.

Speaking at the opening of the bargaining conference of the SA Commercial, Catering and Allied Workers' Union, Vavi said two decades ago it would have been unthinkable for more than 3000 mainly black young people to march on Cosatu House. It would have been unthinkable that a political party such as the DA could celebrate May Day and draw a bigger crowd than Cosatu at some of its rallies, he said.

Vavi warned that the ANC-led tripartite alliance should "wake up and smell the coffee".

"Don't underestimate the fact that already 5% of the blacks in the townships are voting for the DA ... it is not a small matter, it is not about promoting the opposition, but it is about 'vuka maw'lele' [catch a wake-up].

"Don't beat the messenger [let us] look [at] ourselves in the mirror," Vavi said to thunderous applause.

"The army of unemployed is the African youth in particular, blacks in general and women. [Zille] is trying to [present herself] to this marginalised section of the population that is beginning to lose hope because we seem not to have a solution to their crisis of unemployment," Vavi said. - Additional reporting by Sapa

BIRTHDAY WISHES FOR WORLD'S GREATEST LEADER

• "Happy birthday Madiba. The whole nation loves you dearly" - President Jacob Zuma

• "On behalf of the people of the United States, we would like to extend our heartfelt congratulations to Nelson Mandela on the occasion of his 94th birthday and the fourth annual Nelson Mandela International Day" - US President Barack Obama and his family

• "Happy birthday, Nelson Mandela. Thank you for your inspiration to everyone striving for freedom around the world #Madiba" - Britain's Foreign Secretary William Hague

• "In today's world, there could be no better inspiration from one human being" - Manchester United defender Rio Ferdinand

• "Happy birthday to Madiba. He is definitely one of a kind and the exception that proves the rule" - Adele Levinger

• "We pray for your continued good health and happiness. God Bless" - Ebrahim Osman

• "Happy birthday Madiba, the world's most beloved man. We need the thought of your old soul flickering in this moral wasteland we have created" - Margie Orford

• "Happy birthday, Madiba, Thank you for all that you have done for our beautiful country. Congratulations on your 94th cap" -The Sharks