Samsung Electronics Co. Ltd. said it will delay the retail launch of its Galaxy Fold smartphone for an unspecified period of time after reviewers discovered problems with the display, a hit to the reputation of the world's largest handset maker.

Last week, reviewers started posting problems with the device on Twitter, but as of Friday the company did not know the root cause of the screen defects, according to Patrick Moorhead, founder of Moor Insights & Strategy, who said he was in direct contact with the company.

About 50 units of the $1,980 foldable device had been sent for review to journalists, analysts and bloggers in the United States ahead of the launch planned for this Friday, Moorhead said Monday.