Oil and natural gas prices surge, US detention of Iranian ships threatens negotiation prospects.

Oil and natural gas prices spike, as the United States Navy seizes an Iranian ship during this chaotic weekend, and Iran fires on some ships and reasserts control over the Strait of Hormuz. Brent crude prices surged by 7.9%, erasing most of last Friday's losses; European natural gas prices rose by as much as 11%. Iran again blocked the crucial waterway on Saturday, claiming that the US interception of ships related to Iran violated the ceasefire agreement that is set to end on Tuesday. "There is still a risk premium in the market before the deadline, but it is not completely convincing," said Haris Khurshid, Chief Investment Officer at Chicago's Karobaar Capital LP. "If the situation continues to unfold this way, you could see oil prices gradually rise to around $105-115, but there will be a lot of volatility influenced by news during that period."