Far more fun and fire will be provided by some of the other guests, notably F W de Klerk and the outgoing foreign minister, Pik Botha. But if the British dignitaries are briefed properly by the ambassador's staff, they will know that contained in Mr Nzo is a lesson of deep significance: proof that in politics there is life after death.
It was with profound dismay that the news reached diplomatic and ANC loyalist circles on Friday that president-elect Nelson Mandela had selected Mr Nzo to fill the foreign affairs portfolio.
The weekend in South Africa was marked by a multitude of parties to celebrate the birth of the new democratic era. But the very mention of the three-letter word was guaranteed instantly to spoil the fun.
Mr Nzo, 68, was being described by people who know him over the weekend as 'dull', 'listless', 'unprepossessing, to put it mildly', 'brain-dead' and, 'awfully sweet'.
Deposed as ANC secretary-general in 1991 by Cyril Ramaphosa, Mr Nzo was packed off into de facto retirement as head of the organisation's most ineffectual department, Intelligence.
Mr Nzo's job was initially offered, according to ANC sources, to Mr Ramaphosa, an impressive politician, who would have held his own in any diplomatic company. But Mr Ramaphosa, piqued at Mr Mandela's decision to give the vice- presidency to Thabo Mbeki, asked to be excluded from cabinet.
That was another source of irritation at the weekend parties. If the name of the game now, as Mr Mandela has defined it, is to build a great nation, then what on earth was Mr Ramaphosa doing denying his rare expertise to the people on whose behalf he has struggled all his adult life?
He was telling friends at the weekend that he would bide his time to make a comeback. But, amid suspicions that he had opted to put his own power aspirations above the general good, the feeling among the ANC rank and file was one of bitter disappointment.
Nor were many 'comrades' jumping up and down with excitement at the decision of Mr Mandela, in deference to the new ANC dogma of 'non-sexism', to appoint Nkosazana Zuma and Stella Sigcau to the Health and Public Enterprises portfolios.
Mrs Zuma's claim to fame is that she is the charming wife of the ANC's failed candidate for the post of prime minister of KwaZulu-
Natal, Jacob Zuma. Ms Sigcau, a more formidable woman, was overthrown as prime minister of the Transkei homeland in 1988 by General Bantu Holomisa, one of the 252 ANC MPs to be sworn in tomorrow in Cape Town. General Holomisa revealed, after seizing power, that Ms Sigcau had been involved in a corruption scandal over gambling rights in homeland casinos.
Mr Mandela's cabinet is not all gloom and doom. There is no place for his estranged wife, Winnie, and and she is also excluded from a lunch due to be held tomorrow for 1200 VIP guests, to celebrate
the presidential inauguration in Pretoria.