How can I fix my Renault Megane R Reg 98 RTE automatic fuel cut after 60sec?

My renault today on M6 coming back from London developed a strange fault. After every 1 or 2 mintues or 3 to 5 miles the acceleration will die I had to put the car on hard shoulder and turn neutral. when i press race in neutral it would go to high revs but if i put it in gear then it would not move as if lacking fuel. The only way around it was turn it off and back on again.
I had to do this 50 times in last 50 miles. Anybody has a clue what could be wrong. Once restarted the car worked fine for 2 to 3 minutes before dying back again. Thanks as i am clueless about this mysterious fault. The car otherwise is ok and has no faults.