Tatas have decided to hold on to their 32% stake in Idea Cellular, Kishore Chaukar, MD of Tata Industries, said today.He, however, declined to give further details on the future plans for Idea Cellular - the 3-way mobile venture between the Tatas, the A V Birla group and US-based Cingular Wirleless.Sources said Tatas are not averse to buying out, if offered, the 34%stake of Cingular in the joint venture. The department of telecom (DoT) had recently spiked the bid of a consortium of Singapore Technologies Telemedia (STT) and Telekom Malaysia to acquire the Cingular Wireless stake in Idea for regulatory reasons.