Crisis continued to deepen at cash-starved Jet Airways Tuesday as the airline flew just five planes and the management made desperate attempts to garner emergency funds worth Rs 400 crore to stay afloat even as the lenders remained undecided on extending the lifeline.

While the meeting of the ailing airline's board in Mumbai that went on for over three hours remained inconclusive, officials at the lenders and the government maintained that efforts are on to revive the carrier. However, the carrier's pilots union NAG Tuesday threatened to seek resolution under insolvency law as salaries dues remained unpaid.

As SBI Capital Markets vets the initial bids received for stake purchase in the struggling Jet Airways, the airline's founder and former chairman Naresh Goyal opted out from bidding, sources said.

With uncertainty mounting over the future course for the airline, which has been in operation for more than 25 years, its shares crashed nearly 19 per cent during the day amid reports that the carrier might temporarily suspend operations.

Civil Aviation Secretary Pradeep Singh Kharola said the airline has sought emergency funds worth around Rs 400 crore from banks and that the matter is between the carrier and the lenders.

Briefing reporters in New Delhi, he said Jet Airways was operating only five planes. Government officials said lenders are discussing ways to revive the crisis-hit carrier and fresh funds are likely to be infused shortly.

"Discussions for reviving the airline are underway and nothing has been finalised as of now," Punjab National Bank Managing Director and CEO Sunil Mehta told reporters in New Delhi.

Representatives of various lenders to Jet Airways are also understood to have discussed issues related to Jet Airways with Financial Services Secretary Rajiv Kumar.

Jet Airways has a debt burden of more than Rs 8,000 crore. SBI Capital Markets has the mandate for Jet Airways sale on behalf of the SBI-led consortium of the domestic lenders to the debt-ridden private carrier.

Earlier in the day, sources at the airline said all options would be explored before deciding on continuing with its operations. Shares of Jet Airways plunged nearly 19 per cent during the day's trade amid reports that the airline might temporarily shut down its operations. The carrier has already suspended international operations till April 18.

Jet Airways said it is awaiting "emergency liquidity support" from the SBI-led consortium of lenders to arrest further deterioration in its services. Sources said that Jet Airways CEO Vinay Dube has written a letter to SBI, which is the lead lender, seeking immediate fund infusion of Rs 400 crore.

Dube has said that if funds do not come, then the airline would have to ground its entire operations, sources added.

In the morning, Civil Aviation Minister Suresh Prabhu called for a review of issues related to Jet Airways, including rise in airfares. The civil aviation ministry, in a late evening tweet, said that as instructed by the minister, a review meeting was held under the chairmanship of the secretary.

"Airlines agreed to use lower price buckets for selling tickets in order to keep fares within reasonable limits," it said. NAG's Vice President Aseem Vlianini said the union might approach the National Company Law Tribunal (NCLT) for a resolution.

Entities seeking resolution under the Insolvency and Bankruptcy Code (IBC) should have to first get the go-ahead from the tribunal. The union, which has around 1,100 members, said the airline is only operating around 450 seats per day and that operations would have to be suspended if money does not come in.

Management has said that salaries are to be paid from the additional funding only but SBI has said that salaries would not be part of the funds, according to Vlianini. "I think SBI is not serious (about funding)," he said.

An airline source said the number of pilots have reduced to around 1,300 after about 400 pilots left in the wake of the crisis. "Tuesday alone 23 pilots left the airline," the source claimed, adding that over 100-odd pilots have joined budget carrier IndiGo.

A government official said that approaching the NCLT for Jet Airways is not an option at this stage.

"Right now, the lenders are trying to resolve the issue by seeking bidders for investment. This is not the time for lenders to approach NCLT for resolution," the official said.