China has overtaken the US as the world’s largest net oil importer, a once-in-a-generation shift that will shake up the geopolitics of natural resources, according to the Financial Times.

The US has been the world’s largest net oil importer since the middle of the 1970s, shaping Washington’s foreign policy towards oil-rich hotspots such as Saudi Arabia, Iraq, Venezuela, Nigeria and the Caspian basin.

The shift between Beijing and Washington is still tentative, nonetheless. The energy market will wait for more monthly data before to confirm the swing, in part because tax reasons could have distorted the estimates for December’s net oil imports. US oil companies traditionally cut their net oil purchases at the end of the year to reduce their inventories and, hence, their tax bill.

US net oil imports – defined as crude and refined oil products – dropped in December to 5.98m barrels a day, the lowest since February 1992, according to provisional figures from the US Energy Information Administration. In the same month, Chinese net oil imports – defined also as crude and refined oil products – surged to 6.12m b/d, according to the country’s custom office.

“China looks to have overtaken the US to become the world’s largest net importer of crude and petroleum products,” said Eric G Lee, commodities analyst at Citigroup in New York and first to report on the trend.

US net oil imports in January have recovered significantly from December every year over the past decade, suggesting the US could regain the top slot. China net oil imports in January, already released, rose to 6.30m b/d.

On an annual basis, the US remains the world’s largest net oil importer, but the margin has narrowed significantly. The country’s net foreign purchases of crude and refined oil products dropped in 2012 to a 20-year low of 7.14m b/d. In the same period, Chinese net oil imports averaged 5.72m b/d.

Oil analysts believe that even if January reverses the shift, the US is set to slip to the number two spot after China as the world’s top net oil importer later in 2013 or in early 2014, as the surge in domestic oil production on the back of the shale revolution reduces the need to import crude oil. At the same time, US refiners such as ExxonMobil and Phillips 66 are exporting record quantities of oil products to meet booming demand for gasoline, diesel and kerosene in Latin America and Africa.

US oil production surged last year more than 800,000 b/d, the largest annual increase since the start of the petroleum era in the country more than 150 years ago. The rise in domestic production has allowed the country to lessen its dependence on the Opec oil cartel significantly. But the reduction has been uneven, with Saudi Arabia, Kuwait and other Middle East countries suffering relatively little, while Nigeria and Angola bear the brunt of the reduction.