Royal Dutch/Shell said yesterday it was holding off any decision on its participation in Nigeria's prize deepsea OPL250 oil block until it sees details of its allocation to a rival company.

Chevron Corp won the bid for the acreage over a rival, and by all appearances, much stronger cash offer from Shell, Nigeria's biggest oil producer. Presidential Adviser on Petroleum and Energy Rilwanu Lukman who announced the keenly awaited allocations on Tuesday, said the U.S. major would operate the block in alliance with Shell.

"We want to wait and see what the government is promoting. We want to see the details of the award before making any pronouncement," Kisito Okpere, Executive Director of Shell Nigeria Exploration and Production Co, told Reuters.

Although he did not elaborate on what details Shell sought, industry officials said this referred to the equity structure planned by the government for the four multinational oil companies in the concession.

The two other firms are U.S.-based Ocean Energy and Brazil's Petrobras. The Nigerian government decided the partnerships rather than the oil companies themselves. Sources say Shell may pull out of the group arranged for OPL 250, over what the company considered a slight after making a much higher offer for the block.

Shell had bid $200 million, while Chevron offered no more than $60 million, including a signature bonus of $25 million. A senior Shell official had told Reuters in private just before the bids were announced, that the company would settle for nothing less than OPL 250.

The independent This Day newspaper reported yesterday that the Nigerian government favoured the Chevron bid as a gesture to the incoming administration of U.S. president-elect George W. Bush.

But Chevron Nigeria's chief executive Ray Wilcox told Reuters he believed the overwhelming consideration was his company's track record in deep water operations, notably in Angola and New Mexico.

Nigerian Petroleum Ministry officials said Shell could still get another deep offshore block - OPL 322 - now under litigation. It is not clear when the block will be available for allocation. Nigeria originally put 22 blocks on offer last March. When the bids were opened in July, OPL 250 was strongly contested for. Officials say the concession holds estimated reserves of two billion barrels of crude oil.

The government awarded eight blocks on Tuesday, but Lukman told reporters later that winners of the remaining blocks would be announced by the first quarter of 2001. The blocks are in OPLs 249, 322, 326 in the deepwater, as well as OPLs 233, 452 and 236 on the continental shelf.