China's strong manufacturing base and India's software and scientific skills had massive potential both as a production base and for creating a consumer market.
A combination of the "world's factory" and the "world's back office" will drive global economic growth, Chinese President Xi Jinping said ahead of a rare visit to India on Wednesday, playing down mistrust that has kept the Asian giants apart.
Prime Minister Narendra Modi is determined to build closer relations with the world's second-largest economy, whose leader arrived on Modi's 64th birthday armed with pledges to invest billions of dollars in railways, industrial parks and roads.
"As the two engines of the Asian economy, we need to become cooperation partners spearheading growth," Xi wrote in a column in The Hindu newspaper.
He said China's strong manufacturing base and India's software and scientific skills had massive potential both as a production base and for creating a consumer market.
Xi flew straight to Ahmedabad, in Modi's home state of Gujarat, where the prime minister gave him a bouquet of lilies.
The visit coincides with a slowdown in China's economy, with Chinese companies looking abroad for growth opportunities.
A deal worth $6.8 billion to set up two industrial parks for Chinese investment in India was on the cards, a senior Chinese official said in New Delhi at a separate business event where another $3.4 billion worth of agreements was signed between Chinese and Indian firms.
Further deals worth tens of billions of dollars were expected to be announced on the three-day visit, dwarfing the $400 million invested by China in India over the past 14 years.
Modi is keen on Chinese investment to help balance $65 billion in annual trade that is heavily tilted in China's favour. He is also seeking more access for India's IT services and pharmaceuticals to China.
The leaders may also discuss working together on civilian nuclear programmes and seek a solution for a long-running travel visa row, Indian officials said.
Modi hopes the leaders of the world's two most populous nations will establish a personal rapport to match the warmth he shares with Japanese Prime Minister Shinzo Abe, who wished him happy returns in a phone call on Wednesday morning, Indian media reported.
But beyond the smiles and the commercial embrace, ties between nuclear-armed India and China are marked by competition for energy and regional clout as well as a festering border dispute that led to a brief war 52 years ago.
Days before the two leaders shook hands and smiled in Ahmedabad, friction emerged over an alleged Himalayan border incursion by China and over a pact between India and Vietnam to explore for oil and gas in parts of the South China Sea claimed by Beijing.
In his column, Xi said the "Chinese Dragon" and the "Indian Elephant" both cherished peace and shared one of the most dynamic and promising bilateral relations of the 21st century.