The All Parties Hurriyat Conference chairman Maulvi Abbas Ansari resigned on Wednesday.
APHC, a collection of Kashmiri oufits fighting for freedom, is currently engaged in a high-profile dialogue with the Indian government.
Ansari said he stepped down down to "forge unity in the Kashmiri political separatist camp."
The APHC executive met in Srinagar in the morning at its Rajbagh headquarters. The meeting was presided over by Moulvi Ansari. Immediately after the meeting, he announced his resignation and later
flew to Delhi.
The Mirwaiz has been authorised by the APHC executive to "work for larger unity [in APHC] and bring back to the Hurriyat fold some of the estranged executive members including Syed Ali Shah Geelani, JKLF chairman Mohammad Yassin Malik and Peoples League chairman Shiekh Abdul Aziz," Moulvi Ansari said.
"Mirwaiz will start meeting senior separatist leaders from tomorrow," Prof Abdul Gani Bhat told this correspondent at his residence.
Political observers in Kashmir see Moulvi Ansari's resignation as a clear invitation to "Syed Ali Shah Geelani and others to return to the APHC fold."
Geelani currently heads a breakway faction of the APHC.
"We want to broadbase the separatist conglomerate and close our ranks so that we are better placed in the ongoing dialogue with New Delhi. Solution to the Kashmir problem lies in talks," Prof Bhat said.