If the proposals of these airlines are approved, the Kathmandu-Delhi route will see at least 10 flights daily, producing more than 1,500 seats one-way. The additional flights may ignite fierce competition and benefit consumers, according to travel trade entrepreneurs.

While India's full-service airline Vistara and low-cost airline GoAir are preparing to fly to Kathmandu for the first time, budget carrier Spice Jet will be resuming its service which was suspended in 2014, said Tourism Under-Secretary Pramod Nepal.

Nepali private carrier Shree Airlines has been cleared by the Tourism Ministry to fly on the Kathmandu-Delhi sector and is awaiting clearance from the Civil Aviation Authority of Nepal.

"We have received applications from Vistara and Spice Jet," said Nepal. "These two airlines have applied for daily flights, and we are currently processing their applications." He said that Indian budget carrier GoAir reportedly plans to connect Kathmandu too.

Vistara, a joint venture between Tata Sons and Singapore Airlines, commenced operations in January 2015 making its inaugural flight between Delhi and Mumbai. Spice Jet started scheduled flights to Kathmandu as its first international destination in 2010.

Anil Manandhar, corporate manager of Shree Airlines, said they planned to launch Kathmandu-Delhi flights this year. "The traffic on the sector is good," he said, adding that competition would obviously become intense.

New Delhi is the major gateway for flights to Nepal, accounting for nearly 25 percent of the 4.34 million annual air passenger movements to and from Nepal.

The route is considered a lucrative sector as flight occupancy reaches more than 95 percent during the peak season, said Shyam Raj Thapaliya, managing director of Osho World Travel Nepal.

"If you look at the October and November flight status on the Delhi-Kathmandu route, it's almost sold out," said Thapaliya. "It may be due to the occurrence of the festival and tourist seasons in Nepal. At other times too, the sector is very busy."

Travel demand is so high, 1,500 seats daily are not enough, he added. "Nepali students and patients going for medical treatment occupy most of the flights to New Delhi. Besides, more Indian tourists are visiting Nepal."

This season, the cost of a one-way economy ticket on the route started at Rs8,000 and went up to Rs29,000, according to travel agents. "The usual airfare for the hour-long flight is Rs10,000, so it is a very profitable route for airlines," said Thapaliya.

Tourism Ministry officials said that the additional flights would increase competition and benefit consumers with cheaper flights. "It will also vitalise the tourism industry by bringing in more visitors to the country."

After India's Jet Airways suspended its Nepal's flights in April, many carriers have been showing interest in the route.

The suspension of services by Jet Airways resulted in a 40 percent reduction in weekly flight capacity. Jet Airways used to fly thrice daily on the Delhi-Kathmandu sector and twice daily on the Mumbai-Kathmandu sector.

Jet's departure proved a bonanza for another Indian carrier Indigo Air with airfares going up to Rs50,000 from the normal Rs15,000 for a one-way trip during the April-May period.

The Tourism Ministry said that it had received a proposal from Kuwaiti carrier Jazeera Airways to conduct daily flights to Kathmandu.