The gasoline-producing unit at Nigeria's 650,000 barrel-per-day Dangote refinery has been taken offline due to catalyst leaks and other issues, with repairs expected to take at least two weeks, two sources familiar with the matter said.

The refinery's 204,000 bpd Residue Fluidised Catalytic Cracking Unit (RFCCU) has been offline since around August 29, industry monitor IIR Energy said in a note on Tuesday.

The sources requested anonymity to discuss confidential information.

Dangote did not immediately respond to a request for comment.

The massive Dangote refinery has sharply ramped up operations since it opened last year, reshaping global oil and fuel trade flows. The refinery's first exports of gasoline to the United States are expected to reach New York later this month, data from ship tracking service Kpler showed.

However, the refinery has also struggled with frequent outages. The plant's RFCCU was expected to run at lower rates through October after a string of issues earlier this year, Reuters reported in May.

The anticipated length of the current outage is weighing on gasoline availability in the Atlantic Basin, lifting U.S. refiners' profit margins on the fuel, market sources said, despite the unofficial end of the U.S. summer driving season earlier this week.

The U.S. gasoline futures crack spread - the difference in the price of the fuel versus the price of crude oil - gained nearly 3% on Wednesday to the highest level since August 19. It had jumped more than 8% on Tuesday.