US export price index in July posted the largest monthly decline in 27 months, according to the Labor Department's Bureau of Labor Statistics data released on Friday.

Export prices fell 3.3% in July, marking the largest monthly decrease since April 2020.

While the market expectation for the index was to fall 1.1% in July, it increased 0.7% in June.

"Lower agricultural and non-agricultural prices each contributed to the July decline," the Labor Department said in a statement.

"Prices for US exports rose 13.1% over the past year, the lowest 12-month advance since the index increased 9.6% in March 2021," it added.

US exports account for approximately 10% of the country's gross domestic product.

Import prices also decreased 1.4% in July, marking the first decline since December 2021.

The market expectation for the index was to show a fall of 1%, while it increased 0.3% in June.

"The decline was the largest drop in import prices since the index fell 2.6% in April 2020," the statement said.

"US import prices rose 8.8% over the past 12 months, the smallest over-the-year increase since the index advanced 7.1% from March 2020 to March 2021," it added.