WASHINGTON, Feb 19 (Reuters) - Contracts to purchase previously owned U.S. homes unexpectedly fell in ​January, with realtors blaming ‌low housing inventory.

The pending home sales index ⁠dropped 0.8% last month to ⁠70.9, the National Association ‌of Realtors ‌said on Thursday. Economists polled by ​Reuters had forecast ‌contracts, which become sales after a month or two, ​rising 1.3%.

Contracts ​fell in ‌the Northeast and the densely populated South. They rose in ⁠the Midwest and West regions.

Pending ⁠home sales fell 0.4% from a year earlier.

"With mortgage rates nearing 6%, an additional ⁠5.5 ‌million households that could ‌not qualify for a mortgage ⁠one year ago would qualify at today's lower rates," said Lawrence Yun, the NAR's chief economist. "Unless housing supply increases, these additional potential ​buyers becoming active in the market could simply push up home ​prices." 

(Reporting by ‌Lucia Mutikani; Editing by ​Andrea Ricci)