Oil prices pared gains on Monday, after rising more than 5% earlier in the session, after Iran's military said that its first wave of ​attacks on Israel since a ceasefire in April was over.

However, Iran warned of harsher attacks if Israel continues strikes on Lebanon.

Brent crude futures were up $1.01, or ​1.2% to $94.19 a ​barrel as of 1151 GMT, while U.S. West Texas Intermediate crude futures were up 79 cents, or 0.9%, at $91.33. Prices had gained over 5% after renewed Israeli strikes on Iran and attacks on Lebanon earlier had reduced hopes of an ⁠imminent end to the wider war. Brent has risen 30% since the start of the conflict just over 100 days ago, while WTI has risen 36%. Brent in April touched a peak above $126 a barrel.

Israel hit a petrochemical plant in southwestern Iran that it said was used to produce ballistic missiles, and Iran's Islamic Revolutionary Guard Corps said the country retaliated with a strike aimed at a similar Israeli ​facility in the city of Haifa.

The ‌exchange followed Israeli ⁠strikes on strongholds of Iran-backed ⁠Hezbollah in Beirut over the weekend. Tehran has repeatedly said any deal with Washington to end the conflict must include a halt to Israel's campaign ​in Lebanon.

U.S. President Donald Trump on Monday demanded that Israel and Iran "immediately stop 'shooting'".

Because of the strikes, ‌investors were concerned that flows through the Strait of Hormuz might remain restricted for ⁠longer, UBS analyst Giovanni Staunovo said. Roughly a fifth of the world’s daily supply of oil and liquefied natural gas passed through the Strait of Hormuz off Iran before U.S.-Israeli airstrikes at the end of February unleashed the latest escalation of the Middle Eastern conflict.

On Monday, Iran’s ambassador to Moscow was quoted as saying that the Strait would be open but under conditions to be set by Iran and Oman, including a transit fee. "For markets, the best near-term outcome remains a 'skinny' deal that decouples Strait disruption and active strikes from the underlying sources of disagreement, buying time without resolving them," said Erik Meyersson with SEB Research

OPEC+ AGREES OUTPUT TARGET INCREASE

In the face of the resulting supply crisis, OPEC+ on Sunday agreed its fourth oil output target increase in four months.

Analysts said the decision ‌would have little impact since most members of OPEC+, which groups the Organization of ⁠the Petroleum Exporting Countries and allies including Russia, cannot meet their targets because of the closure ​of the Strait or, in the case of Russia, Ukrainian drone attacks that have eroded its production capacity.

"In the current market, the physical impact of such a decision would be close to zero," Jorge Leon, Rystad Energy's head of geopolitical analysis, said in a note to clients. Refiners have bought ​crude wherever they can ‌find it to substitute the oil no longer flowing through the Strait. Since the conflict started, the ⁠world has lost over a billion barrels of supply.

(Reporting ​by Stephanie Kelly, Helen Clark and Colleen Howe; editing by Christopher Cushing, Edwina Gibbs, Jason Neely and Barbara Lewis)