Opposition parties on Monday expressed their dissatisfaction with the preliminary results of the national census, with Muttahida Qaumi Movement Pakistan (MQM-P) and PPP leaders threatening to stage protests against what they described as "rigged" data.

MQM-P leader Dr Farooq Sattar, rejecting the census results, claimed the census results had been "rigged". He alleged that the population figure for Karachi had been marked down as "it cannot be less than 30 million".

Sattar called for a protest against the 'manipulated' figures.

Provisional census data presented to the Council of Common Interest last week shows that the population of the entire province is 47.9m, with Karachi housing 14.9m people.

Similarly, as the Sindh government rejected the census data, the ruling PPP's senior lawmaker Nisar Ahmed Khuhro alleged that an incorrect population figure been released by authorities for Sindh under a preconceived plan.

Khuro claimed that under the 'plan', the figure of Sindh's population had been marked down so that the portion of financial awards allocated to the province did not have to be increased.

Calling for an all parties conference to protest the statistics, Khuhro said that Sindh would not relinquish its rights.

Leader of the Opposition in the National Assembly Khursheed Shah reiterated the party's demand that the data collected by the statistics division and the Pakistan Army should be compared to get a true picture.

"Noone is satisfied with the census results," Shah said.

PPP leader Manzoor Wassan, too, expressed his reservations regarding the census data and threatened to hold protests.

Calling the census data "suspicious", Qaumi Watan Party (QWP) chief and member of National Assembly Aftab Ahmad Khan Sherpao said that while the population of the Federally Administered Tribal Areas stood at 10m, the results had marked it down to 50,000 people.

On Sunday, opposition parties had voiced serious concerns over the census results.

The PPP, which did not conduct a census in the five years it was in power, had been quite vocal in its criticism of the ruling PML-N for delaying the enumeration exercise beyond 2016.

However, following the release of the data, the party claimed the government had treated the enumeration exercise as a mere formality, adding that no one was satisfied with the way the census was conducted.

Pakistan Tehreek-i-Insaf leaders, too, had voiced their concerns over the 57 per cent increase in the national population. Senator Shibli Faraz said the census had been conducted in a shabby and non-transparent manner.

The Senate Finance Committee is due to meet on Aug 29 for a detailed briefing on the preliminary results of census from the statistics division.