U.S. carbon tariffs, still long way off, draw Asia ire

"If you look at real life, how is it going to be implemented? That's going to be a very complicated matter. I'm not sure people have thought clearly, technically how to make this happen," said Changhua Wu, Greater China Director of The Climate Group, an NGO that helps governments and companies trim carbon emissions.

"In the meantime, there are other stakeholders in the U.S., big companies that operate in China and India. They have their opinions as well. So it's going to be a very complicated picture," she added.

Ultimately, the measures could accelerate the development of domestic carbon exchanges in emerging countries, which have thus far sold most of their carbon abatement tariffs internationally.

"If the Senate approved similar legislation before December, the likelihood of domestic carbon pricing being introduced in Asia potentially increases," said Simon Smiles, Asian thematic analyst for UBS in Hong Kong, who has studied the cost impact of domestic emissions trading and carbon tariffs on Asia firms.

"I continue to see the political expediency of carbon-related import duties. But as the legislation currently stands, the near-term risk of border adjustments based on the amount of carbon in goods imported into the U.S. appears very low."

(Writing and additional reporting by David Fogarty)

(Editing by Ben Tan)