Chinese President Hu Jintao says his country could help forge peace between South Asian rivals, India and Pakistan.
President Hu is due to visit Pakistan on Thursday
Mr Hu told a meeting in the Indian capital, Delhi, that Beijing sought no "selfish gains" in South Asia.
Correspondents say India has always been suspicious of China's close support for Pakistan and its military ties with India's historic rival.
On Tuesday, Mr Hu and Indian PM Manmohan Singh pledged to double their trade to $40bn (£21bn) a year by 2010.
"China welcomes and supports improvement in relations between India and Pakistan," the Press Trust of India quoted Mr Hu telling the meeting of politicians, diplomats and economists in Delhi, a day ahead of his visit to Islamabad.
He said China was prepared to play a "constructive role for the promotion of peace and development in South Asia".
A peaceful and prosperous South Asia was beneficial for the whole world, President Hu said.
He also lauded what he said was China and India's "productive co-operation in many fields".
"Today, both China and India are on the fast track of economic and social development, demonstrating to the world the bright future of the two countries and the promise of a revitalised Asia."
The Chinese president is due to travel to India's financial capital, Mumbai (Bombay), later on Wednesday to continue his push for increased economic ties.
He is the first Chinese head of state to visit India in 10 years.
The two Asian giants have overcome many hurdles in recent years but significant differences remain, including a number of border disputes, correspondents say.
Both India and China have produced staggering economic growth in recent years, but India continues to lag behind on many fronts.
China has a literacy rate of 95%, compared with India's 68%. Indian exports of manufactured goods in the financial year ending last March were valued at $71bn, compared with $713bn for China.
The BBC's Anu Anand in Delhi says China has invested millions of dollars in countries surrounding India, building ports and roads in Burma, Sri Lanka and Nepal.
In Pakistan, our correspondent says, President Hu is expected to discuss a civilian nuclear co-operation deal to balance a similar deal agreed between India and the US which is awaiting final approval by the US Congress.