Volvo Car AB said Thursday that car sales fell 28.3% on year in May as strained supply chains and Covid-19 lockdowns in eastern China hit production.

The company has previously said semiconductor shortages would affect production during the second quarter, though on Thursday it said it has recently seen signs of improvement in supply with gradual easing of restrictions, allowing for a slight improvement in production volumes.

Volvo 0MHW, +1.41% said that demand for its cars remains strong, and that it expects production will progressively increase.

The Swedish auto maker–majority owned by China’s Zhejiang Geely Holding Group 175, +1.93% — said it sold 45,952 cars in May, down from 64,111 in the same month last year.

In Europe, sales fell 24.3% to 18,752 cars, while sales in China dropped 43.8% to 9,488 cars. The company reported a sales decline of 29.1% in the U.S., to 9,372 cars.

Volvo’s Recharge range of fully electric or plug-in hybrid models accounted for 33.6% of all Volvo cars sold globally in May, while fully electric models accounted for 7.9% of global sales, the company said.

“Orders for fully electric Volvo cars continue to increase,” it said.

“However, the lockdowns have impacted production of fully electric cars in the second quarter, and this will negatively affect the share of fully electric cars being delivered in the third quarter.”

The auto maker aims to become a fully electric car maker by 2030.

Write to Dominic Chopping at dominic.chopping@wsj.com