By Marianna Parraga

(Reuters) -Loading of Venezuela’s heavy crude at its main oil ports slowed this week after the U.S. imposed a tariff on trade with countries buying the South American nation’s oil and producer Chevron began reducing its tanker fleet there, according to shipping data and a document seen on Tuesday.

On Monday, U.S. President Donald Trump’s administration published an executive order declaring that any country buying oil or gas from Venezuela will pay a 25% tariff on trades with the U.S. starting in early April.

Washington also extended until May 27 a deadline for Chevron to wind down operations in Venezuela. This includes exports of Venezuelan crude to the U.S.

The two moves temporarily focused Trump’s pressure on buyers of Venezuelan crude other than the U.S., such as China. Planned enforcement methods remain unclear.

As of Tuesday, Venezuela’s main oil port, Jose, operated by state-owned PDVSA, had an empty berth, while three supertankers were loading, according to vessel monitoring services TankerTrackers.com and LSEG and a company document.

No tankers were loading for exports at Bajo Grande, which handles shipments of the heaviest crude grades, the data showed.

About two dozen vessels, mostly supertankers, were waiting to load around Jose while two remained in Venezuelan waters after completing their loads, TankerTrackers.com said, adding that two ships left the country empty since mid-February.

Venezuela exported some 910,000 barrels per day (bpd) of crude and fuel last month, with Chevron already seeing a decline with 252,000 bpd exported, below the 294,000 bpd of January.

The growing bottleneck of tankers might lead to loading and shipping delays in coming days as many customers remain puzzled by the U.S. tariff implementation, especially in China, the largest buyer of Venezuelan oil.

Trade of Venezuelan oil to China stalled on Tuesday due to Trump’s tariff order as traders and refiners in that country waited to see how the order would be implemented and whether Beijing would direct them to stop buying.

Venezuela sent some 503,000 bpd to China in February or 55% of total exports.

While the U.S. gave Chevron seven more weeks to wind down operations in Venezuela, the upcoming termination of its license, which last year allowed it to export some 210,000 bpd to the U.S., has in recent days reduced the number of vessels chartered by the company waiting to load in Venezuelan waters, the data showed.

A total of seven cargoes of Venezuelan oil chartered by Chevron have departed from the country so far this month, compared with 15 in February, the shipping data showed.

PDVSA and Chevron did not immediately reply to requests for comment.

Venezuela, which has said U.S. sanctions on the country amount to an economic war, on Monday accused Washington of violating international trade rules.

(Reporting by Marianna Parraga; Editing by David Gregorio and Stephen Coates)

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