Delta Air Lines (DL, Atlanta Hartsfield Jackson) could resume flights to the Gulf region should deals, akin to that reached with Qatar concerning Qatar Airways (QR, Doha Hamad Int'l) this week, be struck with UAE-based carriers Etihad Airways (EY, Abu Dhabi Int'l) and Emirates (EK, Dubai Int'l).

The US State Department said last week that the Qatari government had agreed to published Qatar Airways' financial reports, which are to be audited by an international firm, in a bid to improve transparency at the airline. Delta, American Airlines, and United Airlines have collectively accused Qatar Airways, along with Etihad and Emirates, of unfairly benefitting from state subsidization to the detriment of international competition.

Speaking to CNBC, Delta CEO Ed Bastian said talks with the Emiratis were set to commence on a similar deal.

"While we appreciate the work done with the Qataris, there is another big area that needs focus, which is the UAE and specifically Emirates and Etihad," said Bastian. "I know those negotiations are starting and we hope the consultations reach a similar conclusion."

Should a final agreement be reached with the UAE-based airlines, Bastian said Delta could then consider resuming flights to the Middle East (excluding Israel which it already serves) as well as India. It withdrew from both markets in 2015 citing the ME3's alleged subsidization for allowing them to undercut its fares.

"We need to have a presence in the Middle East. We need to have a presence in India and other parts of Southeast Asia, which we have been run out," Bastian told CNBC. "By shining a light on the scope of the subsidies and providing transparency, it is going to allow us all to make long-term investment decisions to go into markets knowing that our government is standing behind us."

Although not confirmed, a report by the Associated Press said Qatar Airways had also pledged not to launch any 5th Freedom flights to the United States. Given Emirates already operates two such routes - Newark via Athens Int'l and New York JFK via Milan Malpensa - it is uncertain how these negotiations would proceed.