Over 2.3 lakh requests for mobile number portability (MNP) have been rejected out of a total 8.4 lakh requests till July 31 in Delhi licence service area on various grounds, the telecom ministry said Friday.

MNP, which is a service that allows mobile phone users to switch operators while retaining their phone number, was launched across the country Jan 20, 2011.

"Total 8,39,471 requests for MNP have been received in Delhi licence service area with all service providers till July 31 out of which MNP was allowed in 6,11,179 cases," Communications Minister Kapil Sibal informed the Rajya Sabha in a written reply.

The grounds for rejection of MNP requests included use of wrong unique porting code, subsisting contractual obligations and blacklisted subscriber numbers, among others.

The minister said that 32.43 percent of the requests were rejected because of using wrong porting code, while 23.84 percent were denied the service due to subsisting contractual obligations with exit clause in subscriber agreement to which the subscriber had not complied with.

Over 18 percent of the requests were denied at donor operator network with records that the subscriber number is either blacklisted or has unsettled overdue bills while 14.23 percent of requests had to be turned down as they requested for the service within initial period of 90 days.

As per the MNP regulations and instructions, the MNP requests are to be settled in 7 days except in Jammu and Kashmir, Assam, North East Licence Service Area for which the period is 15 days. Hence at a given point of time, certain number of requests are expected to be in process, the minister said.