The President of the Republic, Filipe Nyusi, on Tuesday asked the High Court in London to block allegations that he accepted illegal payments in the country's case against Credit Suisse and others over the two billion dollar "hidden debts" scandal.

The case of the "hidden debts" triggered criminal investigations from Maputo to New York, as well as a series of lawsuits in London involving Credit Suisse, the shipbuilder Privinvest, its owner Iskandar Safa and many others.

According to a Reuters report published on Tuesday, Privinvest and Safa are trying to drag Filipe Nyusi into the case, arguing that he should contribute to any damages they may be ordered to pay if they are found liable to Mozambique.

Privinvest and Safa's arguments against Nyusi center on payments of 11 million dollars that they say Privinvest made in 2014 to finance Nyusi's successful bid for the presidency and the election campaign of his ruling Frelimo party.

Privinvest and Safa argue that if the payments were not legal and were attributed to Mozambique, then "Filipe Nyusi must be held responsible".

However, the Mozambican head of state says he is entitled to immunity as acting head of state. He was not in court on Tuesday, but his lawyer, Rodney Dixon, argued that "there is no legal difference" between someone trying to sue Nyusi in London or Britain's King Charles in Australia.

Nyusi's request for immunity is the latest twist in the long-running dispute, centered on three agreements between state companies and Privinvest, ostensibly to develop Mozambique's fishing industry and for maritime security.

The deals were financed in part by loans and bonds from Credit Suisse - since taken over by UBS UBSG.S - and backed by undisclosed guarantees from the Mozambican government.

But hundreds of millions of dollars disappeared and when state loan guarantees became public in 2016, donors such as the International Monetary Fund suspended support, causing a currency collapse, debt crisis and years of litigation.