Confronted with spiralling aviation turbine fuel prices, which account for half an airline's operating costs in India, several low-cost and full-service carriers will go for a steep increase in fares that could vary from 5 to 20 per cent, from June 20.

Today's announcement comes three weeks after fares were raised 8 to 10 per cent following a rise in ATF prices (which increased 18 per cent last month).

Earlier this week, state governments had raised serious issues on the airlines' request to lower sales tax, which could be as high as 30 per cent in some states, as a means of reducing cost.

Executives of low-cost carriers SpiceJet and IndiGo said they had increased fuel surcharge by Rs 300 for distances below 750 km and by Rs 550 for sectors over 750 km.  The earlier surcharges stood at Rs 1,950 and Rs 2,250 for below 750-km and above 750-km sectors, respectively.

GoAir executives said they would take a decision on an increase in the fuel surcharge on Friday.

Jet Airways [Get Quote], the country's largest airline, has increased basic fares instead of fuel surcharge, calibrating increases to distances.

Jet Airways CEO Wolfgang Prock Schauer said: "While the basic fare will increase 10 per cent, the overall increase in fare would not be more than 5 per cent since we have kept the fuel surcharge intact."

For distances less than 750 km Jet Airways will have a minimum basic fare of Rs 1,000 and for sectors between 750  km and 1,000 km the minimum basic fare will be Rs 2,250.

For distances above 1,000 km the basic fare will be Rs 3,000. This is an increase anywhere between Rs 100 and Rs 1,000.

Jet Airways' subsidiary value carrier JetLite, formerly Air Sahara, which was acquired last year, will have minimum fares of Rs 500 for distances below 750 km, Rs 1,500 for distances between 750 km and 1,000 km and Rs 2,000 for distances above 1,000 km. Its earlier minimum basic fare started from Rs 100.

Kingfisher Airlines said it was evaluating an increase in fares and would take a decision in two or three days.

State-owned Air India, which was formed by a merger between the two state-owned airlines Indian Airlines and Air India, will have a three-slab basic structure.

For distances below 750 km the basic fare will be Rs 1,000. For distances between 750 and 1,000 km the minimum fare will be Rs 2,350 and for distances above 1,000 km the minimum fare will be Rs 3,000.

"The basic fares have increased by anywhere between Rs 100 and Rs 1,000 depending on sectors," said an Air India spokesperson.

Today's increase means that tariffs on the Delhi-Mumbai sector, India's busiest route, will increase from Rs 4,500 to Rs 5,000 for low-cost carriers and from Rs 5,500 to Rs 6,000 for full-service airlines.