Media mogul Kalanithi Maran and his KAL Airways has bought 5 per cent equity in low-cost air carrier SpiceJet for Rs 91.52 crore, as part of the deal to acquire 37.7 per cent stake in the company signed this June.

This was an off-market transaction, following which the Chennai-based industrialist's direct stake in SpiceJet now has increased to 17.72 per cent, the company said in a filing to the Bombay Stock Exchange.

"This is part of the (June) deal, which every one knows about. Gradually, the stake will be increased to 37.7 per cent through off market transactions over a period of time," a senior official of the low-cost carrier said on the conditions of anonymity.

The Sun TV Chief had clinched a deal to acquire 37.7 per cent stake in June for about Rs 750 crore from its then promoters, American investor Wilbur Ross, his investment companies and the Kansagara family-promoted Royal Holding Services Ltd.

The latest transaction, through which Maran bought 1.93 crore shares (5.03 per cent stake) at a price of Rs 47.25 per piece, is pursuant to the share purchase agreement, SpiceJet filing added.

Maran also has an option to acquire a further of 20 per cent stake through open offer. Earlier, the open offer was supposed to be launched in August and the new promoters are yet to announce fresh dates for it.

The airline, India's second largest low-cost carrier, will flag off its first international flight from Delhi to Kathmandu tomorrow, while the Chennai-Colombo flight will be launched on October 9.

It has a market share of about 13 per cent and has a fleet size of 22 aircraft serving 20 destinations across the country.

Shares of SpiceJet were traded today at Rs 77.25 a piece on the Bombay Stock Exchange, down 0.19 per cent from the previous close.