"OPEC got the message," said Abhishek Deshpande, an executive director at JPMorgan Chase. "The Goldilocks oil price target is just shy of US$70 a barrel, that should quiet the complaints from the consumers."
The hope is that the deal is enough to keep oil just under US$70 a barrel, although Saudi Arabia and other members are focusing on supply and demand, rather than on a price target, said one OPEC delegate.
The vague language in the communique and lack of real targets could allow Riyadh and others to fine tune their production to keep the market in check. The document didn't mention the specific production hike cited by Al-Falih, instead pledging that the group would focus on restoring its output cuts to the level originally agreed in 2016.
OPEC and its allies exceeded their pledged 1.8 million barrel-a-day production cut by 47 per cent last month, according to Russian Energy Minister Alexander Novak. That's about 850,000 barrels a day of additional supply losses that have been largely unintentional, reflecting the collapse in Venezuela's oil industry and long-term declines in Mexican output.
Saudi Arabia has enough spare capacity to offset those losses and keep a lid on prices, but Al-Falih has acknowledged that such a move isn't politically palatable for his fellow OPEC members.
The final communique made no mention of whether the kingdom, or any other member, could compensate for losses elsewhere. Yet it said the group as a whole should strive for "overall conformity" of 100 per cent, which in practice will only be achievable if those nations with spare production capacity step in to fill the gap left by others.
"The lack of specificity is bullish for prices," said Joe McMonigle, senior energy analyst at Hedgeye Risk Management. "It's a mystery oil production increase because we don't really know the final numbers."
Crude actually rallied following the OPEC deal, with US benchmark West Texas Intermediate jumping as much as 4.6 per cent to US$68.43 a barrel.
The vague language may help to preserve the hard-won unity of the group of 24 oil producers, whose cooperation ended a three-year price slump.
It salvages an agreement that was very much in doubt on Thursday evening after Iranian Oil Minister Bijan Namdar Zanganeh walked out of a meeting with fellow ministers, predicting nobody could persuade him to back an increase.
"It wasn't easy, but everyone found a way to navigate the obstacles," said one minister, who asked not to be named discussing the details of the closed-door meeting. "The Iranian resistance was strong and the communique is the art of finding the middle ground."
Iran has bridled at Trump's interventions. Zanganeh has said the US president is to blame for high prices because of his unilateral withdrawal from the international nuclear agreement and the imposition of fresh sanctions that could significantly curb Iran's crude exports.
The deal cements the petro-alliance between Vladimir Putin, the Russian president, and Prince Mohammed bin Salman, the powerful heir to the Saudi throne, which is slowly supplanting OPEC as the main arbiter of the global oil market. The alliance has been successful even as Riyadh and Moscow take different political views in Syria and Iran.
OPEC will meet again on Saturday with non-members, including Russia, to ratify Friday's agreement.
After all the internal wrangling, which for weeks has whipsawed oil markets, the group's president said Friday's deal was ultimately about the needs of oil users.
"This agreement that we reached is a testimony that we care about the consuming countries," United Arab Emirates Energy Minister Suhail Al Mazrouei, who is also OPEC president, told reporters. "We listen when they say that they have a concern."
