* Elections delayed for second time in three months
* Change caused by late census results and rainy season
(Adds detail, background, southern reaction)
KHARTOUM, June 30 (Reuters) - Sudan will delay its national elections by two months to April 2010, said officials on Tuesday, the second postponement of the poll which will be the country's first democratic vote in two decades.
Sudan's National Elections Commission said delays in the release of census details and a decision to postpone voter registration until after the rainy season were reasons for changing the vote timetable for a second time in three months.
"The National Elections Commission has been deliberating and observing the circumstances relating to the national elections and has decided on the modification of the previous timeframe," said a statement signed by Commission chairman Abel Alier.
Africa's largest country was promised democratic presidential and parliamentary elections under a 2005 peace deal that ended more than two decades of civil war between north and south Sudan.
The main parties in both north and south Sudan have in the past said they would resist moves to delay the poll, but the independent commission has the power to set election timetables without the approval of politicians.
Southerners are particularly worried any lag could hit the timing of a long-awaited referendum, scheduled for January 2011, on whether their territory should split away as an independent state.
U.S. special envoy Scott Gration called on Sudan in May to ensure it carried out "credible" elections and pledged Washington's support for the southern independence referendum.
In his May visit to Sudan, seen as a sign the diplomatic detente between Washington and Khartoum may be thawing, he also called for the passage of legislation seen as pre-requisites for a free and fair election and referendum.
BASHIR SET TO RUN
Current president Omar Hassan al-Bashir is expect to stand in the elections, despite a decision this year by the International Criminal Court to issue an arrest warrant against him on charges of atrocities in Darfur.
No other candidates from the main parties have formally said they will run.
A spokeswoman for the south's dominant Sudan People's Liberation Party (SPLM) said she would need more information on the exact reasons for the delay before commenting.
"If they have postponed to help with rules and regulations for freer and fairer elections or to reach peace in Darfur then it is OK," Keji Jermolil told Reuters.
The north's dominant National Congress Party (NCP), led by Bashir, said members would accept the delay, which would give parties more time to prepare.
"We hope that this will be the last amendment for the timetable," the NCP's chief official for the elections Ibrahim Ghandour told Reuters.
A Commission timetable released on Tuesday pointed to Apr. 5-12, 2010 as the new period for polling, sorting and announcing the results. Voter registration is planned for November 2009 and campaigning will take place from February 4 to Apr.4, 2010.
The elections were previously due to take place in February 2010, and before that, July 2009.
A total of six elections will be held -- for the presidency and parliament, the south Sudanese presidency, state governors, the southern parliament and state assemblies.
Some analysts have raised concerns about the complexity of the planned voting process. (Reporting by Andrew Heavens; Additional reporting by Skye Wheeler in Juba; Editing by Sophie Hares)
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