"There is simply no case for the pressure that we, who have among the lowest emissions per capita, face to actually reduce emissions," Jairam Ramesh, minister of state for environment, told Clinton in their talks.

"And as if this pressure was not enough, we also face the threat of carbon tariffs on our exports to countries such as yours," he added in a statement he made to Clinton in private, repeated to journalists and then handed out to the media.

The comments took some of the shine off an event that Clinton staged at a "green" building outside New Delhi to show the potential of energy-saving technologies.

The red brick building, built by ITC tobacco and hotels conglomerate, maximizes natural light and its glass lets in light but not heat, which respectively reduce the need for artificial light and air-conditioning.

Making her first trip to India as secretary of state, Clinton was, however, upbeat about bridging US-Indian differences on how to curb the greenhouse gas emissions that cause global warming.

"We had a very fruitful discussion today," Clinton told reporters after a one-hour discussion with Ramesh. "We have many more areas of agreement than perhaps had been appreciated."

TECHNOLOGY PACT

The United States wants big developing countries such as India and China, whose emissions are skyrocketing as their economies grow, to agree to rein them in.

Developing countries say industrial nations must curb their own pollution and provide funding to help developing nations before they are asked to set limits that could crimp their economic expansion.

Both sides appeared to be playing to the Indian domestic audience, with Clinton saying Washington did not wish to do anything that would reduce India's growth and Ramesh seeking to blunt criticism his government might concede too much.

Todd Stern, the US special envoy for climate change, accompanied Clinton and will hold talks over the next few days with senior Indian officials.

With a new UN climate treaty due to be agreed in Copenhagen in December, tackling global warming is one of the central issues on Clinton's visit to New Delhi. On Monday she will meet Prime Minister Manmohan Singh and external affairs minister SM Krishna to discuss defence sales, nuclear power and non-proliferation.

US officials expect to sign a pact to ensure that US arms technology sold to India is used for its intended purposes and does not leak to third countries, a step required by US law.

Such a pact would allow US firms to compete for India's plan to buy 126 multi-role fighter aircraft, which would be one of the largest arms deals in the world and could be a boon to Lockheed Martin Corp and Boeing Co.

The United States also hopes India will announce that it has reserved two sites for US companies to build nuclear power plants, which could be worth as much as $10 billion in business for American firms.

And they want to establish a "strategic dialogue" between the two countries to be led by Clinton and Krishna, reflecting US President Barack Obama's desire to strengthen ties with India.