The apparent progress toward resolving the conflict in Libya caused a key global oil price to drop sharply on Monday.

Prices for a barrel of Brent crude oil fell about $3.50 to as low as $105.15 in London trading.

Brent is the benchmark price for about half the world's oil.

Before the rebellion in Libya, the country exported about 2 percent of the world's oil, or about 1.6 million barrels a day. During the conflict, that output has fallen more than 90 percent as oil workers were evacuated and transportation was disrupted.

Worries about export disruptions contributed to a sharp increase in global oil prices. The economic impact of those concerns was magnified by the high quality of Libyan crude oil.

Estimates vary on when Libyan oil exports can resume. One says it will take months, another says perhaps a year.