Zambia’s government on Tuesday rejected claims that President Edgar Lungu had bankrolled a Rwandan rebel leader accused of orchestrating deadly attacks in his country’s border regions.

The claims were made by the rebel chief, Callixte Nsabimana, who is on trial for terrorism and other charges. He has already admitted to working with other foreign governments against Rwanda.

During his latest hearing on Monday, Nsabimana told a Rwandan high court that Lungu had promised his National Liberation Front (FLN) $1 million to help oust the administration in Kigali.

He said Lungu had made a down payment of $150 000 in support of “rebel attacks to remove President Paul Kagame from power”.

In a statement Tuesday the Zambian presidency said it “would like to categorically refute these claims”. It stated “unequivocally that these allegations were false and must be treated with the contempt they deserve”.