The governing ANC had argued that uMkhonto we Sizwe (MK), headed by ex-President Jacob Zuma, had breached trademark law.

But the Durban High Court disagreed, allowing the use of the name, which translates as Spear of the Nation.

It is a significant victory for MK ahead the 29 May general election.

Mr Zuma's supporters cheered and chanted in court after the judgement was delivered.

The ANC has said it will appeal against the ruling.

Last month, the ANC suffered another legal blow in its attempt to stop MK from running in the election, saying it had not met the official registration criteria.

The MK name and logo holds huge political symbolism because of the now-defunct armed wing's role in fighting for the end of white-minority rule in South Africa.

The new MK party may have no chance of winning the election, but it likely to bruise the ANC, which, for the first time since the end of apartheid in 1994, could lose its outright majority in parliament.

Mr Zuma, a former stalwart of the ANC who once served in its armed wing, was South Africa's president for nine years from 2009.

He was forced from power and replaced by current President Cyril Ramaphosa in part over corruption allegations, which Mr Zuma denies.

Visvin Reddy - the provincial leader of MK in KwaZulu-Natal, Mr Zuma's home province where he enjoys considerable support - said it was the best possible news for the party that was launched in December.

He told the TV channel Newsroom Afrika from outside the courtroom in Durban that the ANC's legal challenges to the party's existence showed it was running scared.

In a 42-page ruling, Judge Mahendra Chetty said the ANC's case was really a matter for an electoral court, not the high court.

He added that the high court was also not the forum to "settle a dispute where there are competing historical accounts of events which took place almost 60 years ago, as to who may rightfully lay claim to the name uMkhonto we Sizwe".

When it came to the symbols confronting voters on the ballot paper, the judge said he was of the view that there would be no confusion.

The ANC's trademark over the MK symbol was registered for "education; providing of training; entertainment; sporting and cultural activities", he said.

"It was not entirely clear to me how the use of the mark in political activities" would fall under that category, he added.

But ANC Secretary-General Fikile Mbalula said the trademark was "about legacy" and the party would appeal against the ruling "to stop and prohibit the unlawful use of the ANC's trademarks, symbols, and heritage by Mr Zuma's party".

Earlier this month, an electoral court overturned an electoral commission ban on the 82-year-old former president's candidacy for a parliamentary seat.

The constitution bars people from holding public office if convicted of a crime and sentenced to more than 12 months in prison.

Mr Zuma had been sentenced to 15 months in jail in 2021 for failing to testify in a corruption investigation, though he only served three months on health grounds and was given a remission of sentence by Mr Ramaphosa.

The electoral court has not yet given a reason for its ruling, but Mr Zuma's lawyers argued that the remission meant that his sentence had been "cancelled".

The electoral commission has now lodged an urgent appeal with the highest court, the Constitutional Court, in a bid to overturn the electoral court's verdict.