The PWD has issued a notice to AAP national secretary Pankaj Gupta over its continued occupation of 206, Rouse Avenue as party office.
Sources in the government said that as on May 31, the fine, which is essentially penal rent, amounts to Rs 27,73,802.
The fine amount, which is 65 times the license fee, will pile up further if the party doesn't vacate the premises, the sources said.
In April, the PWD had issued a notice to AAP's National Convenor Arvind Kejriwal asking him to immediately vacate the office, which it said that was allotted in "violation" of rules.
The party had then said that it would seek a legal recourse against this action as other political parties too have been allotted bungalows to use as office space.
The three-member Shunglu committee, formed by the then Lt Governor Najeeb Jung to examine over 400 files pertaining to the decisions taken by the AAP government, had pointed out "irregularities" in allotting the office.
In November 2015, the AAP government had approved a policy for land allotment to state parties.
The Kejriwal government then alloted a bungalow to the AAP on Rouse Avenue the following year.
The bungalow was earlier alloted to Asim Ahmed Khan, the then Delhi minister, who was sacked over graft charges.
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