Ashtead plc, parent company of Sunbelt Rentals, has put its oil and technology business up for sale, according to U.K. Internet publication Times OnLine. The move followed a drop in Ashtead’s stock price to a three-and-a-half year low, with investors fearing its exposure to the U.S. construction market. About 80 percent of Ashtead’s profits come from its Sunbelt Rentals division.

Ashtead appointed NM Rothschild to seek potential buyers, the report said. Rothschild has sent documents on the company to about 50 potential buyers, according to the Times OnLine report.

Analysts in the U.K. have expressed concerns about the debt levels of the Leatherhead, Surrey, England-based company, which also owns U.K. rental chain A-Plant.

The oil and technology division is seen as attractive to buyers because of the current strength of the oil and energy industries.