RBS has upgraded Petronet LNG to 'buy' from 'sell' and raised its target price to Rs 150 from Rs 57. Lower KG-D6 gas production will result in more demand for LNG allowing the firm to run its Dahej terminals at close to capacity,RBS said in a note. The lack of regulation would allow the firm to raise tariffs for regassification,it added. At 1:13 p.m.,shares were up 0.6 percent at Rs 118.