The Calcutta Municipal Corporation (CMC) is mulling a zone in the city with taxes at the panchayat rate.

Residents of Joka, which became part of the CMC area in 2012, could be paying much less in taxes than that of other parts of the city if the civic authorities have their way.

Mayor Sovan Chatterjee said on Tuesday old residents of Joka would pay taxes at the rate the panchayats used to charge them before the area merged with the city civic body.

The areas that were under the Joka-I and Joka-II gram panchayats - covering 18.96sq km - were merged with the CMC as wards 142, 143 and 144 in September 2012.

"We will not increase the tax for the Joka residents. All old residents will continue to pay taxes at the old rate," Chatterjee said on Tuesday.

The CMC tax rates will only apply to those who will buy property in Joka. The rates of property tax in the CMC areas vary between 40 and 60 per cent of the annual valuation of a property.

Tax rates in panchayat areas are generally much lower than the rates in an urban area.

A senior official of the civic body said a similar decision was taken when Jadavpur, Garden Reach and Kasba were added to the CMC in 1984. "The residents of the three areas were allowed to pay taxes at the rate the municipalities used to charged them before the merger," the official said.

The authorities had then said that it would be unjust to ask the residents of the three areas to pay taxes at the CMC rate as they did not enjoy certain civic services that their counterparts in other areas of the city did.

"The old rate continued for a few years after the merger till enough development work was undertaken and a parity achieved," an official said.

However, many pockets in these areas still lack some of the basic amenities, like covered drains and proper roads.

As for Joka, mayor Chatterjee did not specify till when tax at the panchayat rate would be levied.

Sources said the CMC had already spent about Rs 30 crore on development work in Joka. After taking over Joka three years ago, the CMC concentrated on building pucca roads and underground sewer lines.

The Trinamul Congress won all three wards in the civic elections held in April.

Chatterjee said the current CMC board was against increasing the tax burden. The mayor has not proposed any increase in property tax rates in the budget for 2015-16 presented on Thursday.

Opposition councillors have called the budget an "election manifesto" ahead of for next years' Assembly polls and wondered how Chatterjee would raise money to carry on with development work.