NEW DELHI, Dec 31 - India will introduce mobile number portability across the country by March 31, 2010, pushing back its introduction by up to 3 months in parts of the country, the government said in a statement on Thursday.

Mobile Number Portability (MNP), which allows users to retain their number even if they switch operators, was to be introduced in metro cities and the so-called Category A telecom zones from Dec, 31, and in other areas by March 20, 2010.

The government has now decided to implement it in whole of the country in one go, by 31st March 2010, the Ministry of Communications and Information Technology said in the statement. (Reporting by Devidutta Tripathy, Editing by John Mair)