"At COP26 we need to define what blue hydrogen means, because if you have blue hydrogen with little CO2 capture and a lot of methane leakage, it is very damaging," CEO Marco Alvera told the Saudi Green Initiative forum in Riyadh.
"Blue hydrogen must be defined, has to be certified, so the people producing very low or no carbon and no methane leaking in the hydrogen can have a tradable market," he said.
Italy's Snam makes most of its revenue from gas transport but has signed a flurry of hydrogen deals over the last year.
Governments and energy companies are placing large bets on hydrogen helping lower greenhouse gas emissions, but its future uses and costs are highly uncertain.
Blue hydrogen is extracted from natural gas using steam-methane reforming, currently the standard process, and captures the CO2 emissions in underground or subsea storage.
It is seen as a transitional approach while green hydrogen, which uses renewable energy for extraction, cannot fully meet demand. Some environmentalists oppose it.
Alvera also said he hoped COP26 would help get consumers involved.
"We need to get Amazon to start certifying net zero products. That will create a big offset market," he said, noting this would also require a means of certifying the supply chain of products.
(Reporting by Yousef Saba in Riyadh and Marwa Rashad in London; editing by Peter Graff and Jason Neely)
By Marwa Rashad and Yousef Saba