Here are the 10 updates in this big political story:
Najeeb Jung, 65, a graduate of the London School of Economics, former bureaucrat and the 13th Vice-Chancellor of Delhi's prestigious Jamia Millia Islamia University, had taken over as the Lieutenant-Governor of Delhi, replacing Tejender Khanna, in July 2013.
A statement from Najeeb Jung's office today said he thanked the people of Delhi for their "support and affection, especially during the one year of President's Rule in Delhi".
Delhi was under President's Rule since Chief Minister Arvind Kejriwal stepped down in February 2014 after his 49-day government, after being prevented from tabling his Jan Lokpal Bill in the legislative assembly.
AAP had blamed Mr Jung for sending the draft Jan Lokpal bill to the law ministry, which insisted that the Centre's nod was needed to pass the bill.
In its second tenure, Mr Kejriwal's AAP, which swept to power in Delhi in February 2015, alleged that as the Centre's representative in Delhi, Mr Jung used his veto to strike down several crucial government decisions.
The friction between the Delhi government and the Lieutenant Governor's office had started 2 months after the new government took over, when Mr Jung refused to route files on police, public order and land through him in response to Mr Kejriwal's order.
The Delhi government clashed with Mr Jung after he appointed senior bureaucrat Shakuntala Gamlin as acting Chief Secretary in June 2015, and over the appointment of the chief of the Anti-Corruption Bureau and Delhi women's commission chief Swati Maliwal.
Earlier this year, a Delhi High Court verdict stamped Mr Jung's primacy as the administrative head in Delhi. But AAP challenged the order in the Supreme Court, which, in the last hearing said an elected government "should have some power", otherwise it cannot function. The next hearing of the case is in January 18 next year.
Today, Mr Kejriwal said he was surprised by Mr Jung's decision to quit. His deputy Manish Sisodia said despite the "bitter-sweet experience", "together with Najeeb Jung, we have good job for Delhi".
The BJP claimed Mr Jung had quit as he was "upset" with the AAP government. The Congress speculated if Mr Jung had been he removed "to bring someone who close to the RSS (BJP's ideological mentor Rashtriya Swayamsevak Sangh)".
Delhi Airport Becomes 1st To Achieve Net Zero Carbon Emission Status "Financial Means Not Sole Ground To Decide Child's Custody": Court Video: US Diplomat, Vlogger Explore Delhi's Iconic Pre-Independence Eateries 150 mg Semen In Kolkata Doctor's Body, Suspect Gang-Rape: Parents To Court 2 French Rafale Jets Collide Mid-Air, Instructor, Pilot Missing Independence Day Updates: "75,000 New Seats For Medical Students In Next 5 Years", Says PM Modi Probe Reveals Brazil Plane Crashed One Minute After Pilots Sensed Trouble "Strictest Punishment For Crimes Against Women": PM Amid Kolkata Protests "Working To Reduce Government Interference In People's Lives": PM Modi Track Latest News Live on NDTV.com and get news updates from India and around the world.