Smartphone vendors concerned about the strong performance of the iPhone 4S are to wait until the second quarter of 2012 to launch new handsets.

That's according to Taiwan-based sources in the smartphone supply chain quoted by Digitimes, who say that Samsung, HTC, Nokia and LG lack the confidence to launch their new models at the moment after record sales of the iPhone last month and the first quarter of 2012 expected to see strong sales of Apple's latest handset, the iPhone 4S, too.

Instead, the vendors will unveil new handsets at the Mobile World Congress show in Barcelona at the end of February, with these new models going on sale in the second quarter of 2012.

Apple is thought to have plans to unveil a sixth-generation iPhone at some stage this year, possibly in the third quarter, according to Morgan Stanley's Katy Huberty. Presumably the same vendors aren't too keen to launch their new handsets around the same time as a new iPhone comes out either.