UNITED NATIONS (Reuters) - U.N. Secretary-General Ban Ki-moon on Tuesday welcomed Ivory Coast's publication of a provisional voter list, which he described as a key step in organizing the country's long-delayed presidential election.

"(Ban) believes that with this important development, the Ivorian parties and institutions have made significant progress towards the establishment of a consensual and transparent voters list," the U.N. press office said in a statement.

Presidential elections in the world's top cocoa producer, still scarred by a 2002-03 civil war that divided it in two, have been delayed five times since 2005 in a tortuous peace process.

The United States called on Ivory Coast on Tuesday to hold the presidential election as soon as possible, saying it was disappointed a vote originally set for later this month had been delayed.

"It is imperative that all parties take every measure to ensure that elections are held without further delay," State Department spokesman Ian Kelly said in a statement.

Ban's statement echoed that, saying the West African country must now "prepare the final voters list and move forward in determining a new election date as soon as possible."

Officials in Ivory Coast confirmed this month the presidential vote originally set for this Sunday would be pushed back, the latest in a series of delays over rebel disarmament and identifying voters.