American oil exports are surging thanks to "bargain basement prices" for U.S. crude, but rising output elsewhere in the world could put a lid on the U.S. shipments, according to Matt Smith, head of commodity research at tanker-tracking firm ClipperData.
The United States shipped a record 1.3 million barrels of oil overseas in the week through May 26. Exports have hit a number of all-time highs this year as rising U.S. oil production pushes down prices for futures, the benchmark for U.S. crude. That makes the country's supplies attractive to foreign buyers.
However, a rebound in oil production in Nigeria and Libya threatens to put downward pressure on the price of international benchmark , Smith said. That would chip away at U.S. oil's discount and make overseas buyers think twice about buying American barrels, he said.
"If we see those come closer to parity then that will stop those exports, that will keep more crude in the U.S. and then we keep prices around these kind of mid-40s levels," he told CNBC's "Squawk Box" on Thursday.
The price difference between Brent and WTI has grown this year, but the spread between the two benchmark contracts has narrowed this month.
The U.S. Energy Information Administration on Tuesday forecast American output will rise to 9.3 million barrels a day this year and a record 10 million barrels a day in 2018. That would potentially keep a lid on WTI prices.
On Wednesday, investment bank UBS said it believes a correction in oil prices is underway as OPEC production cuts are "more than offsetting the vigorous rebound in U.S. shale production."
OPEC members Libya and Nigeria are both exempt from the cartel's agreement to remove 1.8 million barrels a day from the market. That deal aims to reduce huge global stockpiles and prop up prices.
Nigeria's production capacity returned to normal levels Wednesday, ending 16 months of limits on some fuel grades after last year's attacks on energy infrastructure by militants.
Libya's output has recently recovered above 800,000 barrels a day for the first time since 2014, as the country make progress toward political reconciliation between rival factions.
Analysts have cautioned political risk in both countries remains elevated. Renewed hostilities in either nation could lead to another drop in oil exports.
Heightened tensions among OPEC members after a breakdown in diplomatic relations between Qatar and a Saudi-led group have also raised concerns about the group's output deal and its ability to make deeper cuts if necessary.