Mehbooba has accepted Singh's resignation, party sources said.
Singh resigned from the ruling PDP on October 22, accusing the party of ignoring Jammu region and not taking action on his demand for deportation of Rohingya refugees from the state.
He had also demanded that birthday of his grandfather Hari Singh, the last Maharaja of Jammu and Kashmir, be declared a holiday.
"It is no longer possible for me to be part of a party that continues to disregard the demands and aspirations of Jammu region," Singh had written in his resignation letter to the PDP president.