New Delhi, Dec 13 (IANS): India, China and the US - three countries that share a major chunk of the world population and GDP between them - should institutionalise their partnership and conduct a trilateral dialogue to foster deeper engagement with the world on crucial issues like climate change and terrorism, experts said here Saturday.

Addressing a conference "Shaping the 21st Century: India, the US and China", organised by the Deccan Herald, the experts said challenges like the Ebola virus outbreak and the threat from the Islamic State terror group cannot be tackled by any single country but have to be faced together.

Minister of State for External Affairs Gen. (retd) V.K. Singh said economic dependence will dictate future relations between the countries over the next two decades.

He said the next two decades would prove exciting, with the three countries assisting others to come to higher levels of growth.

On India-China relations, the minister said there was "enough space" for both to grow.

"Both can co-exist, the markets allow for growth. Both have strong relations which are growing," he said.

While there was "discord" regarding the border issue, efforts were on for securing peace and tranquility, he said.

Chinese envoy Le Yucheng said the accord inked between China and the US on climate change last month showed how two big powers can cooperate for peace and development of the world.

He said the world was facing challenges like Ebola, the IS threat and the turmoil in Ukraine, which no single country can deal with alone.

"So we cannot afford any warfare between us. We need to join hands to address the challenging reality of the world," Le said.

Congress leader Jairam Ramesh said the three countries together comprise 35-40 percent of the global population and are the three largest economies with their combined GDP at 40-45 percent of the world.

He said China was the fastest growing economy, India the fastest growing democracy and the US the fastest growing developed country.

"The three have a role to work as a trio to address the major problems of the world," Ramesh said.

He said the climate change accord between the US and China was an example of how they can address differences and agree on major issues.

Ramesh said that besides climate change, the three could also discuss nuclear non-proliferation, which was an important issue with the emergence of non-state actors.

"It falls upon the three to come out with a no first use doctrine," he said.

The three could also coordinate on tackling regional and international terrorism.

India, China and the US while working together should also assure the world that their deepening engagement was not aimed at them and relations should not be viewed as a zero sum game.

"The three need to take initiative and institutionalise the mechanism for dialogue," Ramesh said.