Apple’s suppliers are preparing to manufacture the company’s largest-ever iPad, with production scheduled to commence by the first quarter of next year, according to sources.

The new iPad will have a screen measuring 12.9 inches diagonally, they said .

Apple currently produces iPads with 9.7-inch and 7.9-inch displays. The company has been working with suppliers for at least a year to develop a new range of larger touch-screen devices, said the sources.

Trudy Muller, a spokeswoman for Apple, declined to comment.

Apple chief executive officer Tim Cook is working to shake up the iPad line. Sales of the tablets, which are Apple’s second-biggest product by revenue after the iPhone, have declined for two straight quarters amid a lack of new models and as consumers have instead gravitated to smartphones with bigger screens.

Apple’s suppliers recently started manufacturing an updated 9.7-inch screen iPad, and were also set to enter production of a new version of the iPad mini, people familiar with the plans have said, with the devices set to be available later this year .

Apple is also said to increasing the screen size of the iPhone. The company is holding an event on September 9th to debut new bigger-display iPhones . Those smartphones went into mass production in July . The iPhones will come in two new models: one with a 4.7-inch screen and another with a 5.5-inch screen.

- Bloomberg