Hussein said that if Israel had not withdrawn within the 30 days, Iraq would consider what action to take next.
OPEC Secretary-General Ali Rodriguez said he will consult with cartel oil ministers on Tuesday and the group could hold an emergency meeting to decide policy.
The Arab-dominated cartel controls two-thirds of world oil exports and could easily replace lost Iraqi and Venezuelan barrels after cutting five-million barrels of daily production since January last year.
Brent crude oil for May settlement rose as much as $1.44, or 5.5%, to $27.43 a barrel on the International Petroleum Exchange in London, within $1 of a six-month high. Brent has gained 36% this year. U.S. crude futures rose 67 cents to $26.88.
Iraq last week called on Arab nations to cut oil supplies as a way of pressuring the United States to force Israel to end its military incursions into Palestinian territory.
A boycott would be ineffective without Saudi Arabia and Kuwait, who have rejected Iraq's call to use oil as a weapon. Many Gulf States depend on oil revenues for more than two-thirds of government income and cannot afford to stop sales.
In November 2000, Saudi Arabia led the adoption of a pledge by OPEC and other major exporters that oil would not be used as a political weapon.
