On the heels of a historic agreement between the U.S. and China to phase down super greenhouse gases known as hydrofluorocarbons using the Montreal Protocol, India now has an opportunity to join the other leaders to secure the most immediate and significant climate protection available to the world through 2020.

More than 110 countries have expressed support, including Russia, South Africa and the EU 27, as well as the U.S., Canada and Mexico, many island states, and other developing nations, but India’s support will be important for a swift conclusion. Secretary of State John Kerry will be in India next week and should make securing India’s support a priority.

President Barack Obama and his administration have embraced the phase-down of climate-damaging HFCs under the Montreal Protocol, making the HFC agreement with China’s President Xi Jinping a priority outcome of their first summit, along with progress addressing the threat from North Korea. Putting climate protection as one of their top priorities is historic and may turn out to be the most important development yet to reduce the world’s climate threat.

The Obama-Xi agreement builds on Kerry’s earlier efforts in China to form a climate task force. Secretary Kerry also made the HFC phase-down under the Montreal Protocol a priority of his participation in the Arctic Council summit last month, bringing Russia into the growing consensus. This follows the success of former Secretary of State Hillary Rodham Clinton who made phasing down HFCs a key part of the Rio+20 summit declaration, supported by more than 100 heads of state. Clinton also made reductions of HFCs part of the Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants, which she launched in February 2012.

India now has the chance to join the U.S. and China as a leader to complete the consensus needed to amend the Montreal Protocol in October. Reluctance risks leaving India on the sidelines as China and the U.S. develop their special relationship.