HARARE: A key ally of Zimbabwe Prime Minister Morgan Tsvangirai pleaded not guilty Monday to terrorism charges of trying to topple veteran President Robert Mugabe.

Asked by high court judge Chinembiri Bhunu how he would plead, Roy Bennett, a former white farmer who is treasurer to Tsvangirai's party, said "not guilty my lord".

Attorney General Johannes Tomana said the charges against Bennett arose between 2002 and 2006, claiming that he was the chief financier in a deal to buy arms to topple Mugabe.

Bennett is accused of providing 5,000 dollars to purchase weapons including eight Uzi rifles, 19 grenades and six stun grenades.

"The accused, Roy Bennett provided money to (key state witness) Peter Michael Hitschmann for the procurement of weapons," Tomana said in his submissions to the court while reading out the charges.

"The accused person was the financier of the said firearms. The accused devised a plan of assassination of certain individuals."

Tomana said that apart from the "illegal grand plan, radio communications links were also to be dis-enabled."

Defence lawyer Beatrice Mtetwa said the charges levelled against her client were concocted by his political rivals to stop his joining the unity government.

"He will contend that his prosecution constitutes continued persecution by his political rivals who are trying to stop his participation in the inclusive government," Mtetwa said during her submissions.

The trial continues Tuesday.

On Friday, defence lawyers applied for the judge to recuse himself from the case, alleging bias towards the prosecution, but the judge ruled against the application Monday.

The same charges against other officials in Tsvangirai's Movement for Democratic Change (MDC) have already been tossed out of court. Bennett could face the death sentence if convicted.

His arrest last month prompted Tsvangirai to stage a three-week boycott of the unity government.

Tsvangirai and his long-time rival Mugabe formed the power-sharing government in February, nearly a year after disputed polls that saw Mugabe handed the presidency in a one-man run-off.