BEIJING, May 9 (Reuters) - China's oil imports in April fell to their lowest level in nearly four years, as the closure of the Strait of Hormuz affected supplies to the world's largest oil importer.

Data released by Chinese customs on Saturday indicated that crude oil imports fell 20 percent in April to 38.5 million tons compared to the same period last year, marking their lowest level since July 2022.

China imports nearly half of its crude oil needs from the Middle East, and the closure of the strait is causing a decrease in the number of tankers carrying oil and refined products to the rest of the world.

Chinese data released today does not differentiate between seaborne and pipeline oil supplies. However, data from ship-tracking firm Kpler indicates that crude imports by sea reached 8.03 million barrels per day, also the lowest level since July 2022.

Despite the decline in imports, estimates from ship-tracking firm Vortexa concluded that crude inventories grew by 17 million barrels in April, but said those inventories would fall in May.

The turmoil in the Middle East has prompted China to impose strict controls on exports of refined products such as gasoline and jet fuel to protect its domestic market.

This policy led to a decline in exports of refined petroleum products in April to their lowest level in nearly 10 years, recording 3.1 million tons, a decrease of about a third compared to March levels.

This may still overestimate the quantities destined for customers in Asia and elsewhere because the data includes shipments to Hong Kong, which is typically a major destination for Chinese refined products and exempt from export controls.

Natural gas imports also fell 13 percent to 8.42 million tons, but the data does not differentiate between liquefied natural gas (LNG) transported by sea and gas transported by pipeline. China imports significant quantities of LNG from Gulf countries.

China's crude oil imports during the first four months of the year were still 1.3 percent higher than in the same period last year, reaching 185.3 million tons.