RIYADH, 5 June — A technical problem between Baghdad and the United Nations has delayed the reopening of the main Saudi-Iraqi border crossing at Arar, closed since Iraq’s 1990 invasion of Kuwait, a Saudi customs official said yesterday.

The border post was due to have opened for trade last week, but Iraq and the UN, which supervises all imports into the Arab country, have so far failed to reach agreement, the official said.

"We are ready for the opening any time. But Iraq and the UN have failed to resolve some technical differences. We are waiting for the green light to operate the crossing," the official told AFP, speaking on condition of anonymity.

A Saudi exporter, meanwhile, said the world body wanted a UN official posted at the Iraqi side of the border to supervise the imports under the oil-for-food program, a request Iraq has so far rejected.

Iraq wants the UN official to be posted on the Saudi side of the border as is the case with its frontiers with other countries.

The customs official expected the standoff to be resolved in the coming few days. Over the past 12 years, the post was opened only occasionally to allow Iraqi pilgrims into the Kingdom.

Saudi exports to Iraq under the oil-for-food program — introduced in 1996 to allow Baghdad to sell crude under UN supervision to meet the humanitarian needs of its sanctions-stricken population — are currently sent through Jordan.

Saudi businessmen say exporting directly to Iraq will save them between eight and 10 percent in operating revenues.

Iraqi Trade Minister Mohammad Mahdi Saleh has said Baghdad has imported more than $1 billion worth of goods from Saudi Arabia within the framework of the humanitarian program.