Gul had claimed that Anderson tampered with the ball during Pakistan's tour of England last year and Broad did it too in the Ashes series in Australia.
Cook, before leaving with the team for the ODI series in India, asserted that Anderson and Broad have not tampered with the ball.
"We certainly have not tampered with the ball and if he did have any complaints, he should have gone to the ICC (International Cricket Council) over that," Cook was quoted as saying by the daily Telegraph.
"I think he (Gul) has almost said himself that it has been a bit of a mountain out of a molehill."
Gul had said: "During our series against England last year I saw Anderson was doing it (ball tampering). Against Australia, when they (England) won the Ashes, everyone saw Broad use his shoe to scratch the ball."
Meanwhile, Cook reckoned that it will be "incredibly tough" to beat India in the five-match away series, beginning October 14 in Hyderabad.
"I certainly think we can beat India," Cook said.
"It will be incredibly tough. We need everyone to be playing very well. We all know what the one-day crowds are like over there. They love their cricket."
"Delivering our skills when 50,000 or 60,000 people are screaming and when balls are flying all over the place will also be a key factor, but certainly with this squad I think we can do something really special."