By Ben Blanchard

BEIJING (Reuters) - China's government is giving no details on the trial of shamed senior leader Bo Xilai, the final chapter in its worst political scandal in decades, as speculation mounted the case could be heard as early as Monday.

A Beijing-backed Hong Kong newspaper, the Ta Kung Pao, reported on Friday that Bo's trial would begin on Monday in the southern Chinese city of Guiyang.

But the government has not confirmed or denied this, belying recent efforts to promote transparency and openness, and at least two well-informed sources said on Sunday the reports were not true.

However, a third source, who has ties to the leadership, said the trial would in fact begin on Monday in Guiyang.

It was not immediately possible to reconcile the conflicting reports. Reuters reporters in Guiyang said they could see no signs of heightened security so far, either around the main courthouse or in any other part of the city.

Once a contender for China's top leadership, Bo was ousted from his post as Communist Party chief in the southwestern city of Chongqing last year following his wife's murder of a British businessman, Neil Heywood.

Bo, 63, was widely tipped to be promoted to the party's elite inner core before his career unraveled. The downfall came after his former police chief, Wang Lijun, fled briefly to a U.S. consulate for last February and alleged that Bo's wife, Gu Kailai, had murdered Heywood with poison.

Gu and Wang have both since been convicted and jailed.

No criminal charges against Bo have yet been revealed, only accusations from the party of corruption and of bending the law to hush up Heywood's killing.

Bo was last seen in public in March and is being held in custody, though there has been no word where he is being held and he has not been allowed to defend himself in public.

China's new Communist Party chief Xi Jinping, who takes over from Hu Jintao as president in March, has made government accountability and fighting corruption two of his key themes since assuming his party role in November.

The party has also tried to show it is at least paying lip service to following legal procedures in pursuing the case against Bo.

"If they are doing this by the book and the trial is on Monday then there should have been a formal announcement by now," said Zhang Lifan, a Beijing-based political commentator. Continued...