Apple may return to the metal back for a new iPhone model that will have an LCD display, according to a report.

Nikkei's sources claim that the new 6.1-inch LCD iPhone, due out in 2018, will come along two other more expensive handsets equipped with OED displays sized at 6.3 and 5.8 inches.

Apple launched three new models this year, with iPhone X being its first model to adopt an OLED display. All three handsets sport glass backs with either aluminum or stainless steel frames. The company's iPhone 8 and iPhone 8 Plus are equipped with LCD screens.

Foxconn, Catcher Technology and U.S.-based Jabil are listed as the current suppliers for iPhone metal casings and frames.

Currently, Samsung Display is Apple's sole supplier of OLED panels for its devices. But LG Display is another possible supplier for flexible OLED panels during 2018. China's BOE Technology Group, Japan Display and Sharp are not yet in position to supply Apple next year.

Sharp and Japan Display are currently among the basic Apple suppliers for LCDs.