Oil prices rose on Thursday after US strikes on Iran and renewed Israeli threats against Tehran revived concerns about disruption to Middle East supplies, while comments from Russian President Vladimir Putin signalling openness to peace negotiations limited the gains.

Brent crude futures were up 15 cents, or 0.16%, at $95.78 a barrel by 1700 GMT while US WTI crude futures rose 63 cents, or 0.69%, to $91.64. Both contracts were heading for their fourth day of gains and hit six-week highs earlier in the session.

Israeli Defence Minister Israel Katz renewed warnings that Israel would “cripple” Iran’s military and civilian infrastructure, including energy facilities, if Tehran launched attacks against it.

Putin said on Thursday there was a chance of reaching an agreement to end the war in Ukraine. Speaking at an economic forum in Russia’s far east, he said a number of countries including the US and China were ready to support a peace settlement.

Meanwhile, Iran added ships to the list of vessels it deems non-compliant and subject to fines, confiscation or detention if they try to sail through the strait.