Prosecutors in South Africa are set to announce whether they will drop corruption charges against African National Congress leader Jacob Zuma.
Mr Zuma is widely expected to become the country's next president after elections later this month.
He is accused of graft, racketeering and money-laundering in connection with an arms deal signed with western companies in 1999.
The 66-year-old denies the charges and says they are part of a political plot.
Mr Zuma was first charged in 2005, but has yet to face trial.
The charges have twice been put on hold - most recently in September 2008, when the judge ruled that there had been political interference in the case while Mr Zuma's rival for party leadership, Thabo Mbeki, was president.
The National Prosecuting Authority (NPA) successfully appealed, but Mr Zuma then lodged a legal request for the charges to be reviewed.
South Africa is expected to come to a standstill briefly on Monday as people tune in to hear the NPA's decision broadcast live on radio and television.
The BBC's Mpho Lakaje in Johannesburg says state prosecutors and Mr Zuma's lawyers have been locked in meetings in recent weeks.
The ANC leader's legal team has submitted new information it says proves there was political meddling in the case against him, adds our correspondent.
It is believed to include taped conversations of those involved in the alleged plot.
The South African press has widely reported that the prosecution will not proceed with the case.
If this is true, an outcry is expected from other political parties.
They have previously condemned any move to drop charges against the ANC leader, saying it would be a clear interference in the judiciary by the government.
Opposition Inkatha Freedom Party leader Mangosuthu Buthelezi told the BBC: "If the charges are just dropped when there is no trial it seems to me the stink of what they accused him of will not go away."
There is no presidential immunity in South Africa, but the idea of taking the president to court is something few prosecutors would relish, our correspondent adds.
South Africa will hold presidential elections on 22 April.
