HARARE (Reuters) - Zimbabwean Prime Minister Morgan Tsvangirai's ally Roy Bennett went on trial accused of terrorism on Monday in a case that has stoked tensions in the unity government of Tsvangirai and President Robert Mugabe's ZANU-PF.

After initial arguments, the trial was adjourned to Wednesday by High Court Judge Muchineripi Bhunu to allow time to consider applications made by the state and defence.

Bennett, whom Tsvangirai wants to bring into the government, was arrested in February and charged with illegally possessing arms to commit acts of terrorism, banditry and insurgency, charges that carry a possible death penalty.

The state brought several cases of ammunition and rifles to be presented as evidence in the court in Harare on Monday.

"This is a very serious matter which must be awarded the amount of seriousness it demands," Zimbabwe's Attorney-General Johannes Tomana told the court.

Bhunu will rule on Wednesday on a state application to dismiss Bennett's defence outline after state lawyers argued it was improperly presented. He will also rule on an application by the defence to stop a key state witness from testifying.

Prosecutors plan to call Peter Hitschmann, a former policeman in Ian Smith's minority-white ruled Rhodesia, as a star witness.

Defence lawyers argued Hitschmann's testimony would contradict a sworn affidavit and statements he made to the High Court in 2006 and that he had also told his lawyer that he was not prepared to be a state witness.

Hitschmann was jailed in 2006 for illegal possession of dangerous weapons but the High court threw out the more serious terrorism charges. He was released in July this year.

Before the adjournment, a tense-looking Bennett sat in the dock, at times with his head bowed.

"Obviously I have been persecuted since I joined politics and I have been living in persecution since then. You never know when you are going get justice," Bennett told journalists as he left the court.

Tsvangirai's Movement for Democratic Change (MDC) says the case is politically motivated and the party briefly boycotted the unity government after Bennett, a white former coffee farmer, was detained in prison following his indictment for trial.

Bennett, the MDC treasurer, has denied the charges and the MDC says the case was designed to stop him from taking office as deputy agriculture minister.

The MDC says Mugabe is frustrating efforts to swear in Bennett, along with other senior MDC officials, as required by a political agreement signed last year between the rival parties.

Mugabe says he does not oppose Bennett becoming a minister but says he should be acquitted by the courts first.

A senior Tsvangirai aide said Mugabe had previously told the former opposition leader that Bennett's nomination was "provocative", especially after an often violent land seizure drive that saw white commercial farmers, including Bennett, losing their land.

In 2004 Bennett was sentenced to 12 months in jail after he was convicted of assaulting a ZANU-PF minister during a parliamentary debate.

Bennett, a one-time policeman under Ian's Smith's white-ruled Rhodesia, returned to Zimbabwe in early 2009, shortly before his arrest, after spending two years in exile in South Africa.

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