Two weeks after cancelling Delhi network of Air Odisha and Air Deccan, the civil aviation ministry is likely to soon cancel four more sectors of the two carriers involving 41 routes across Raipur, Chennai, Mumbai and Bhubaneswar sectors, said sources familiar with the matter.

The participants of the first round of government's ambitious regional connectivity scheme UDAN or Ude Desh ka Aam Naagrik have still not started operations on these sectors after numerous extensions of deadline, sources privy to the matter told CNBC-TV18.

"No one knows when they will start operations. A Sharjah-based investor has provided Air Odisha a helping hand but still, they haven't started operations. Now, they have told us that they will start operating from December first week but it is a dicey situation," one of the sources said on condition of anonymity.

The letter of termination for routes across the four sectors has been sent by UDAN's nodal agency, Airports Authority of India (AAI), to the civil aviation ministry and the ministry is likely to approve the letter in 1-2 days, the source added.

Among the routes likely to be cancelled are Air Odisha's 12 connections around Bhubaneswar including Bhubaneswar to Jharsuguda, Jharsuguda to Ranchi, Bhubaneswar to Rourkela, 10 routes on Raipur sector such as Utkela to Raipur, Utkela to Bhubaneswar, Raipur to Jagdalpur and 11 on Chennai sector comprising Bengaluru to Salem, Salem to Pondicherry, Chennai to Neyveli, Chennai to Kadapa among others.

The proposed termination of the network will also include Mumbai sector of Air Deccan, which has eight connections such as Pune to Ozar( Nasik), Mumbai to Kolhapur and Mumbai to Jalgaon.

In the first round of UDAN, the government had awarded four sectors to Deccan Charters Pvt Ltd or Air Deccan and five to Air Odisha Aviation Pvt Ltd. Out of these nine sectors, the aviation ministry had cancelled the Delhi sector of both the carriers late October.

With the proposed termination of the four sectors, three would be left and for those, AAI is sending notices to the airlines again.

"We are in the process of sending notices to Air Deccan and Air Odisha for their sectors across Gujarat, Shillong and Kolkata," another source aware of the matter said.

Gujarat sector of Air Odisha includes 10 routes such as Mundra to Ahmedabad, Ahmedabad to Jamnagar, Ahmedabad to Mithapur(Dwarka) and the airline. Air Deccan's Kolkata sector and Shillong sector comprise a total of 18 routes.