"Double speak of Mufti of J&K exposed on issue of music being Un-Islamic. All Religious Fundamentalists are experts of Double Speak," Singh wrote on Twitter.
The grand mufti could not be immediately reached for his reaction on Singh's comments.
However, Ahmad had on Saturday termed the video as handiwork of mischievous elements.
"It was not a musical event. It was a seminar on life of noted literary person Akbar Haideri which was organised by Aziz Hajini and Rukhsana Jabeen (Director AIR Srinagar). The programme began with recitation of Holy Quran and at the end Kaiser Nizami read some of the verses of Akbar Haideri," he said.
He said the news reports about the video were an attempt to tarnish his image.
The video showing Ahmad enjoying music, an act he had termed as forbidden in Islam, went viral on Saturday and drew sharp reactions from the netizens.
The Grand Mufti is seen in the video in the company of several other persons, including women, at a gathering where a local artist is singing ghazals while playing harmonium.
Ahmad drew widespread criticism for his presence at the musical event as he had issued a "fatwa" (religious decree) against the first all girls rock band of Kashmir saying singing was "un-Islamic".
The three-member band decided to disband the rock group following the fatwa issued by the Grand Mufti in January this year.
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