Vavi said the ruling party had landed itself in a "very dangerous place" and needed to do some serious introspection to salvage its losses and improve the lives of ordinary citizens.

The warning was given a day after thousands of DA supporters marched on Cosatu's headquarters in Braamfontein, Johannesburg. The march ended in chaos following violence between DA and Cosatu supporters.

In a keynote speech at the trade union federation's international policy conference, in Kempton Park, on the East Rand, Vavi warned against the ANC's policies which, he said, were failing the poor and unemployed.

Criticising some of the ruling party's recent controversial decisions - including the reinstatement of crime intelligence chief Richard Mdluli - Vavi said the ANC must focus on the poor and not on fights for leadership.

The ruling party will in December hold an elective conference in Mangaung at which President Jacob Zuma is expected to fight for re-election.

"South Africa as a country is sitting on a ticking bomb that one day will explode ... Another 1976 is waiting to happen.

"If we preoccupy ourselves with palace politics while Rome is burning, then history will judge us equally and harshly."

Vavi's critique of the ruling party was sparked by Tuesday's march by DA supporters - mainly black youths - in protest at rising unemployment and the government's failure to introduce a youth wage subsidy.

"A country that has this magnitude of unemployment in the midst of this opulence workers see every day, a country that tolerates for 18 years those kind of inequalities to just grow and grow and deepen, and with the poverty that not only grinds but humiliates such a huge number of the population - we are sitting on a ticking bomb indeed."

Earlier this month, the International Labour Organisation released statistics that showed that unemployment in South Africa was at 23.9% and that 70% of the unemployed were between 15 and 34.

Vavi warned that, if radical policy changes were not effected, the ANC could see the D A gaining more sympathy from the working class.

"If we don't stop the real crisis, then those 3000 [DA marchers] will become 6000.

"It will eventually succeed. Eventually all of us will be in very, very hot water in no time."

In addition to the DA's march, Vavi said the intensity of violent service delivery protests should be a sign that South Africans are losing faith in the ANC's policies.

"That ticking bomb is starting to explode, judging by the number of service delivery protests all over the country.

"Unless we break with what is currently unfolding - I'm not an alarmist - we may see [the events that have been] unfolding in Europe in the past two years being revisited here in South Africa."

The ANC will hold its policy conference next month. This will be an opportunity for it to address these issues.

"It can't be business as usual. We offer nice rhetoric but in practice we are not very different.

"We can talk about the Freedom Charter and this history and nice things we hear about now, but in essence there is no difference in the content."

Cosatu - which was instrumental in pressuring the ANC into delaying the controversial e-tolls, which would have hit motorists hard in the pocket - said unemployment was still too high.

"Is this not a reality that a growing number of those 72% unemployed in the country are beginning to lose hope because they have been waiting for far too long? If they are losing hope they find new heroes," said Vavi, referring to the sea of blue T-shirted DA supporters who descended on the Johannesburg city centre on Tuesday.

He said the march was significant and that nobody could claim that the thousands of black DA supporters were ill-informed and there merely to support "the white madam".

Describing the march as a "very critical thing that happened", Vavi said it boiled down to the fact that "an empty stomach has no ideology, has no logic, no rationality. [A] stomach is desperate.

"[For] me, the significance of that march is far bigger because the DA has seen the need for itself to exploit this desperation of the most marginalised ."

While Vavi was launching his vitriolic attack on the ANC, President Jacob Zuma, in a response to a DA parliamentary question, confirmed that Cosatu remained the stumbling block to the implementation of the youth wage subsidy scheme.

DA parliamentary leader Lindiwe Mazibuko said: "This is a president who is afraid to make the tough choices that would benefit so many unemployed young people.

"So what is the hold-up?

"Why does the president need to seek further buy-in from Cosatu?"