Oil would be above $120 without OPEC - Lukman

ABUJA, Oct 23 (Reuters) - Oil would already have surpassed $120 a barrel if OPEC did not exist to moderate the price with its spare capacity cushion, a top Nigerian official said on Tuesday.

Rilwanu Lukman, a long-time OPEC Secretary-General and now honorary adviser on energy to the Nigerian president, also criticised a bill in the U.S. Congress seeking to sue OPEC for high prices.

"In spite of what the Americans are trying to do to OPEC, people look to OPEC to moderate prices," he told journalists at a briefing in Abuja.

"If OPEC did not exist, prices would run away to $100, $120 or higher," he said.

The U.S. Senate in June approved a plan that would enable the federal government to take legal action against OPEC for price manipulation, but the White House has threatened to veto the measure.

"It is up to OPEC member countries to take action to protect their interests in the eventuality that this bill becomes law," Lukman said.

The oil exporters' group, which controls about one third of global oil, agreed last month to lift supplies slightly from Nov. 1 in response to rising prices. But prices have kept rising and hit a record $90 a barrel on Friday.

OPEC has blamed the rally on market speculators, rather than any shortage of oil supply.

OPEC oil ministers are expected to meet informally at a heads of state summit of the group in Saudi Arabia next month, before their next formal conference in on Dec. 5.