Zimbabwe's ruling party has formally expelled a former ally of President Robert Mugabe for announcing plans to challenge the leader in next month's election.

Simba Makoni addresses a press conference in Harare, 5 Feb 2008

The party's secretary for legal affairs, Emmerson Mnangagwa, said Wednesday that former Finance Minister Simba Makoni expelled himself by entering the race.

Makoni had been loyal to the ruling Zimbabwe African National Union-Patriotic Front. But he announced Tuesday that he would run in the March election as an independent.

Makoni said he had consulted party members and activists throughout Zimbabwe before deciding to run.

Also Wednesday, a Zimbabwean election monitoring group, Zimbabwe Elections Support Network, said authorities have made what it called a "mockery" of new election laws in effect since January. The group said the laws are regularly broken, including a new media law that demands state media give all contesting candidates and parties equal treatment.

The group also said new voting districts created by the government violate the country's constitution. It said President Mugabe specifically violated the constitution in January by proclaiming elections without allowing parliament to inspect or debate details of the new constituencies.

Mr. Mugabe has been the country's only leader since independence in 1980. The opposition blames him for food shortages and an incredibly high inflation rate.

The opposition recently said it failed to unite behind a joint candidate and will now field separate candidates from two factions.