The global oil glut will grow even larger and may last for a long time, closely followed oil analyst John Kilduff said Thursday.
"We have a ways to go" before oil bottoms, said the founding partner of Again Capital, an alternative investment manager specializing energy and metals.
"There's a new wrinkle to this bearish market almost on a daily basis, ... whether it's Iran ramping up exports or the worsening conditions in China," Kilduff said on CNBC's "Worldwide Exchange."
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He said Iran, which has just rejoined the export market, has discounted its official selling price for European customers to compete with Russia and Saudi Arabia. "India especially is [also] stepping up to resume purchases in a big way of Iranian oil."
In this massive market share battle, which now includes the re-entry of U.S. crude exports, Kilduff said there's skepticism among traders about whether Iran will be able to deliver after being barred from international markets for so long because of sanctions over its former nuclear program.
"[But] I would totally caution against not believing in them," he said, referring to Iran. "They can do it. There's a ton of floating storage. The ability to ramp up their infrastructure to achieve this ramp-up in exports is easily done."
Meanwhile, Gluskin Sheff Chief Economist David Rosenberg told "Worldwide Exchange" in a later interview that when oil finally bottoms "a lot of other things are going to follow suit fairly dramatically."
Global equities remain under pressure, with another sell-off in Europe earlier this week. But according to Rosenberg, that might be divorced from the health of the overall European economy.
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"Are the markets overdoing it? I would say that they probably are at this stage," he said. "It's really about the economy," which has not been that bad in the euro zone.
"If there's one region around the world that doesn't get enough press for putting in some decent economic data ... it's been the euro zone," Rosenberg said. "You can argue that the markets are ignoring it."