Harare  - Roy Bennett, the top pro-democracy official pursued by Zimbabwean secret police over an alleged plot to assassinate President Robert Mugabe, slipped quietly into Zimbabwe early Friday after nearly five years in political exile, sources in his Movement for Democratic Change party said.

Officials who requested anonymity said Bennett had flown from Johannesburg to lend support at a critical meeting of the MDC's national council Friday to MDC leader Morgan Tsvangirai's decision this week to participate in a long-stalled transitional power-sharing government with Mugabe.

The MDC meeting could reverse Tsvangirai's decision, a move that observers say could scupper the implementation of the proposed government of national unity.

The MDC has refused up to now to agree to the proposal until major demands are met, including the equitable allocation of ministerial portfolios and the release of 30 activists abducted and tortured by state security agents over the last three months.

The sources said Bennett, the MDC's national treasurer, encountered no difficulty when he arrived at Harare airport at 8 am (0600 GMT).

"The immigration officer said, 'Oh, it's you Mr Bennett," and gave him a big smile," one source said.

Bennett was driven immediately to the MDC headquarters for a meeting of the party's national executive, preceding the national council meeting.

Bennett, a former white farmer who was driven off his land in eastern Zimbabwe about eight years ago, is adored by many of the country's rural and urban blacks, but loathed by Mugabe's regime. In 2004 he was sent to jail for eight months by parliament after he shoved one of Mugabe's ministers for calling his ancestors "murderers and thieves." His conviction was internationally denounced as wildly excessive.

A few months after he was released, the secret police were after him again, accusing him of involvement in an alleged plot to kill Mugabe. Fearing he would be framed, he slipped into Mozambique and travelled to South Africa where, after a lengthy legal battle, the government granted him political asylum. Observers say the Mugabe regime has a long history of persecuting opposition figures with trumped-up charges.

Tsvangirai dropped his opposition to joining the transitional government on Monday under pressure from regional leaders at a 14- hour emergency summit of the Southern African Development Community, the 15-nation regional alliance, which has been mediating between the two parties but is widely seen as backing 84-year-old Mugabe who has been power for nearly 29 years.

If the MDC national council backs Tsvangirai, he will be due to be sworn in as prime minister of the new transitional government on February 11. The MDC won parliamentary elections in March last year and Tsvangirai won more votes than Mugabe in the simultaneous presidential election, but not enough for outright victory.

Mugabe was declared the winner of a run-off in June after a brutal campaign that left at least 180 MDC supporters murdered and thousands maimed and made homeless. Tsvangirai withdrew from the poll, which was also roundly condemned, including by observers from SADC and the African Union. Mugabe remains president in the new government. (dpa)