TIMELINE: Zimbabwe's presidential election run-off

(Reuters) - Here is a chronology of the main developments since Zimbabwe's presidential, parliamentary and local elections took place on March 29.

March 30 - Opposition Movement for Democratic Change (MDC) claims victory based on early results.

March 31 - Results of parliamentary ballot start to emerge. Regional observers say vote was fair but express concern over delay to results. Western countries also concerned at delay.

April 2 - Final parliamentary election results show ZANU-PF has lost its parliamentary majority for the first time since independence in 1980.

MDC says its leader Morgan Tsvangirai also won presidential election and calls on President Robert Mugabe to concede. State-owned paper the Herald says no candidate won an outright majority.

April 13 - Regional leaders at a summit in Zambia call for the rapid verification and release of poll results.

April 14 - High Court rejects an opposition request to force authorities to release the presidential election results.

April 15 - An opposition general strike to demand the release of results flops.

April 26 - Mugabe's party fails to reverse its parliamentary election defeat after a partial vote recount.

May 2 - Electoral body says Tsvangirai won most votes in the presidential election, but not enough to avoid a run-off against Mugabe. Opposition rejects the result.

May 10 - Tsvangirai says he will return home to Zimbabwe to contest the run-off even though he believes we won outright.

May 16 - Run-off is set for June 27.

May 19 - Opposition accuses military intelligence agents of a plot to kill Tsvangirai, forcing him to postpone his return to the country. The government dismisses it as a propaganda stunt.

May 24 - Tsvangirai returns to Zimbabwe and says Mugabe wants to decimate opposition structures before the run-off.

May 29 - Mugabe says his government had bought 600,000 metric tons of maize to ease food shortages.

June 3 - Zimbabwe has ordered CARE International to suspend operations after accusing it of political interference.

June 4 - Police release Tsvangirai after holding him for more than eight hours while campaigning for the run-off.

June 5 - Police detain U.S. and British diplomats after halting their convoy north of Harare. Their cars were damaged and the diplomats were detained for several hours.

June 12 - Zimbabwe police arrest MDC Secretary-General Tendai Biti. Police say he will be charged with treason and could face the death penalty. He is released on bail on June 26.

June 22 - Tsvangirai says he is pulling out of the run-off.

June 23 - U.N. Security Council unanimously declares a free and fair presidential election run-off impossible.

June 26 - Tsvangirai says there can be no negotiation with Mugabe if he goes ahead with a one-man election.