MELBOURNE, May 1 (Reuters) - Oil rose on Friday as efforts to resolve the Iran war remained at an impasse, with Tehran still blocking the Strait of Hormuz and the U.S. Navy blocking exports of Iranian crude. 

Brent crude futures for July were up $1.04, or 0.94%, to $111.44 per barrel by 0421 GMT, while West Texas Intermediate futures had risen 41 cents, or 0.39%, to $105.48 per barrel.

Both benchmarks have posted gains across four straight months, with Brent's June contract, which expired on Thursday, hitting $126.41 a barrel, the highest since March 2022. 

Oil prices have been on the rise since the end of February when the U.S. and Israel attacked Iran, resulting in the closure of the Strait of Hormuz and the disruption of shipments of around one-fifth of the world's oil and liquefied natural gas supply. Brent gained 50% in March alone. 

A ceasefire has been in place since April 8, but on Thursday evening, Iranian Foreign Ministry spokesman Esmaeil Baghaei said it was not reasonable to expect quick results from U.S. talks, according to the official IRNA news agency. 

"Expecting to reach a result in a short time, regardless of who the mediator is, in my opinion, is not very realistic," he was quoted as saying. 

Earlier in the day, a senior official of Iran's Revolutionary Guards had threatened "long and painful strikes" on U.S. positions if Washington renewed attacks on Iran, pushing oil prices to intraday peaks before retreating. 

U.S. President Donald Trump was scheduled to receive a briefing on Thursday on plans for a series of fresh military strikes on Iran to compel it to negotiate an end to the conflict, a U.S. official told Reuters.