Sales of Hyundai Motor and its sister firm Kia Corporation have declined in the U.S. market in the first half of the year.

Hyundai Motor Group sold over 369-thousand Hyundai cars and over 333-thousand Kia vehicles in the U.S. from January to June for a total of nearly 702-thousand-900 units.

The figure is down by 12-point-seven percent on-year.

The decline is attributed to production disruptions affected by chip shortages as other carmakers have also recorded an average 20 percent drop in sales.

Meanwhile, eco-friendly vehicles saw a sharp boost in sales.

Hyundai and Kia sold close to 90-thousand-700 green cars in the first six months, up 82 percent from the same period last year.

Electric vehicles sold over 34-thousand-500 units, a whopping 317 percent increase on-year, while hybrid EVs sold 55-thousand-900 units, up 35 percent. Two-hundred-71 fuel cell EVs were also sold in the first half, more than double last year's figure.