A crude oil vessel

Nigeria has displaced Mexico as the fourth largest supplier of crude oil to the United States, data from the Energy Information Administration shows.

A Reuters report said U.S. imports of Nigerian crude last week jumped to 559,000 barrels per day (bpd), a weekly record going back to mid-2013 as refining firms turned to imports of West African crude that had previously been displaced by domestic grades during the U.S. shale boom.

Apart from toppling  Mexico , Nigeria is also reportedly competing with  Iraq and Colombia, as largest US crude supplier,  EIA data shows.

Of the 11 cargoes of Nigerian crude that have arrived in the United States this month, eight went to the East Coast, while the remainder were sent to the U.S. Gulf Coast, according to Thomson Reuters Trade Flows data.

Along with typical cargoes of Nigeria’s Qua Iboe, Bonga and Forcados, two 500,000-barrel cargoes of Usan medium crude were delivered to Royal Dutch Shell at South Louisiana Port, marking the first time since May 2014 that this crude has entered the United States.

“More WAF (West African) and North Sea cargoes have been heading to the U.S. as light crude outputs decline,” consultancy Energy Aspects wrote in a note last week.

U.S. shale production in April is expected to fall by 106,000 bpd to 4.87 million bpd, the second-largest monthly decline on record, according to the EIA’s latest drilling productivity report.

From 2004 to 2007, Nigeria exported over 1 million bpd to the United States, but a surge of U.S. domestic production that is of similar quality – including shale oil – later forced African light sweet crude producers, especially Nigeria, to find new destinations for their exports.

In consequence, the United States only imported some 58,000 bpd from Nigeria in 2014 and 2015, the EIA data say.