The United States remained Vietnam's biggest importer in January with revenue of over 2.35 billion U.S. dollars, up 16.2 percent year-on-year, said General Department of Vietnam Customs on Wednesday.

Vietnam's major export commodities to the United States during the period include garment, footwear, wood and its products, phones and accessories among others.

Garment topped the list with the revenue of 954.5 million U.S. dollars, accounting for 30 percent of Vietnam's total export revenue to the United States, up 20.9 percent year-on-year, said the department.

Despite ranking the fifth in the list with 126.9 million U.S. dollars, Vietnam's phone and accessories exports to the United States posted the most dramatic increase of over 10 times compared to that of the same period of 2013, according to the department.

Vietnam saw decreases in some farm export products to the United States in January, including coffee, pepper, rubber, and tea.

Local insiders said on the Vietnam Industry and Trade Information Center website on Wednesday that Vietnam's farm exports to the United States will face further difficulties in 2014 as the Washington is discussing whether to uniformly apply Farm Bill 2012's Catfish Inspection Program, thus creating more obstacles for Vietnamese exported pangasius (tra) fish.