Zimbabwean Prime Minister Morgan Tsvangirai's party has formed a coalition with two other opposition parties in a bid to bolster their chances to challenge President Robert Mugabe and his party in the upcoming general election, local media reported Monday.

Tsvangirai's Movement for Democratic Change (MDC) established the partnership with Mavambo Kusile Dawn (MKD) led by Simba Makoni, a former ally of Mugabe, and Zanu-Ndonga, which was represented by its chairperson Reketai Semwayo.

Zimbabweans will go to polls on July 31 to elect one president, more than 200 law makers and nearly 2,000 local government councilors.

Among the five candidates registered for the presidential election, incumbent President Robert Mugabe and Tsvangirai are considered the serious contenders for the post. Both politicians have just launched their campaigns and unveiled manifestos.