VIENNA, Sept 17 (Reuters) -

The United States is taking a wait-and-see approach on whether to tap its Strategic Petroleum Reserve to stabilize oil markets after weekend attacks on Saudi Arabia's oil infrastructure, Energy Secretary Rick Perry said on Tuesday.

U.S. President Donald Trump said on Monday it looked like Iran was behind the attacks on Saudi oil plants but stressed he did not want to go to war. The attacks sent oil prices soaring and raised fears of a new Middle East conflict.

Washington said over the weekend that if necessary it would tap the SPR - the world's biggest supply of emergency crude oil, which contains roughly the amount the United States consumes in a month. It has not done so yet.

"With regard to energy markets, the president has directed me to release oil from the Strategic Petroleum Reserve if that is needed to offset any potential disruptions," Perry told reporters on a visit to Vienna.

"But looking at the supply numbers we are confident that the markets remain well supplied."

Asked whether the United States might not draw down the SPR at all, Perry said: "Oh absolutely. 'If needed' is a pretty flexible term."

The attacks cut 5% of world crude oil production. Two sources briefed on state oil company Saudi Aramco's operations said it might take months for Saudi oil production to return to normal. Earlier estimates had suggested it could take weeks. Perry would not be drawn on any U.S. assessment.

"I don't know if anyone can give you with clarity - less than, let's say, 72 hours, to be safe, from when this event occurred - the length of time," he said.

"We've in open-source reporting heard, of course, two to three weeks ... to repair the damage. So I would suggest that until you see a different story in the open press, you would be better served to contact someone in the kingdom."