Japanese mobile operator NTT Docomo said Friday that the launch of a new smartphone operating system to rival Google's Android and Apple's iOS had been pushed back owing to development delays.

The open source offering called Tizen, based on the Linux operating system, is the product of a tie-up between companies from Japan, China, South Korea, Europe and the United States.

The consortium that makes up Tizen Association include Docomo, US giant Intel, Japan's Fujitsu, South Korea's Samsung and LG, China's Huawei, and European mobile carriers Vodafone and Orange.

Docomo's president had previously said he hoped the new system would launch by the end of the current fiscal year to March.

But that timeline is being pushed back because Docomo is still "developing products that would maximise the features of the Tizen", company spokesman Jun Otori told AFP.

Tizen is among a handful of new smartphone platforms expected to hit the market this year to challenge the stranglehold of Android and iOS.

The systems account for more than 90 percent of the smartphone market, with BlackBerry and Microsoft's Windows Phone vying for third spot.

Phones using operating systems based on the open-source platforms Linux and Mozilla's Firefox are due out this year, most likely in emerging markets.