Sony has announced that its 2011 fleet of Ericsson branded Xperia smartphones will receive an Android 4.0 Ice Cream Sandwich (ICS) upgrade this month.

The smartphone maker said the rollout will start mid-April for the Xperia Arc S, Neo V and Ray. Other handsets including the Xperia Arc, Play, Neo, Mini, Mini Pro, Pro and Active will get the update at the end of May or early June.

Sony said: "Our developers have been hard-at-work to ensure we’re on track and the highest standards are met to deliver you the best possible user experience on Xperia 2011 smartphones with the upgrade to Android 4.0 platform release."

However, with the good news is a warning to users. Sony said that because ICS is a powerful operating system (OS) it will require more resources and could "impact performance in some user scenarios."

One of the main things Sony is concerned about it the increase of RAM usage in ICS. The Xperia range has 512MB RAM which could struggle with certain apps and tasks.

The upgrade to Google's latest OS will not be via the traditional over-the-air (OTA) method. Users will have to upgrade with the Companion software for PC or Bridge for Mac. Sony wants users to make a "conscious and informed decision to upgrade, so that you continue to enjoy optimum experiences from your Xperia smartphone."