The Appeal Court in Chad has upheld a three year prison sentence imposed in July on an opposition member of parliament, Ngarledjy Yorongar.

The jail term was set after Mr Yorongar was convicted on defamation charges arising from allegations of corruption against the parliamentary speaker Wadal Abdelkader Kamougue in relation to an oil pipeline project.

Mr Yorongar is opposed to plans for the exploitation of oil resources in southern Chad and their export via a pipeline to Cameroon.

Correspondents say that the appeal court verdict is likely to disqualify him from elections due in two years time.

The appeal court did, however, reduce the suspended jail terms and fines imposed on the editor and a reporter of the paper which published his allegations.