Oil prices fell by nearly 2% on Wednesday, after rising earlier in the session, as investors assess the risks of supply disruptions related to the Iran-Israel conflict and possible direct involvement of the United States.

Brent futures lost $1.40, or 1.8%, to $76.73 per barrel at 10:41am ET. American West Texas Intermediate crude fell $1.29, or 1.7%, to $73.55. Both contracts had gained more than 4% in the previous session.

Prices went into negative territory after President Donald Trump refused on Wednesday to answer questions from journalists about the possibility of the United States considering striking Iran or its nuclear facilities, saying that the Iranians had made contact but that he believed that “it is very late to discuss”.

Trump said that Iran had offered to come and negotiate at the White House, without giving further details.

“It basically suggests that Iran could say, 'Alright, we're going to stop our nuclear program, '” said Phil Flynn, senior analyst at Price Futures Group. “That would prevent the United States from entering into a conflict. That would be a reduction in risk.

On Tuesday, Trump warned that American patience was dwindling and called for an “unconditional surrender” of Iran, an option rejected Wednesday by Iran's supreme leader, Ayatollah Ali Khamenei.

While Trump said that he “for now” had no intention of killing Khamenei, his remarks suggested a firmer stand on Iran as he considers increased US involvement.