Indian Prime Minister Narendra Modi has spoken to US President-elect Joe Biden by telephone to congratulate him on his election victory, which he said showed the strength of US democracy, and he vowed to deepen strategic ties.

Modi initially sent his congratulations to Biden in a social media message soon after US television networks projected him to be the winner of the November 3 election even though US President Donald Trump has refused to concede defeat.

Modi followed that up with a phone call to congratulate Biden and reaffirm his commitment to a strategic partnership between the two big democracies, Modi said on Twitter late on Tuesday.

“Prime Minister Modi warmly congratulated US President-elect Biden on his election, describing it as a testament to the strength and resilience of democratic traditions in the United States,” the Indian foreign ministry said.

Modi had built close ties with Trump. The two leaders held a joint rally in the US city of Houston last year and again in Modi's home state of Gujarat this year, during a visit to India by Trump.

Modi's critics said the prime minister had come dangerously close to endorsing Trump's candidature, which they said could hurt India's prospects under a Democratic administration.

India and the United States drew closer during Trump's presidency as both countries aimed to counter China's expanding military and economic influence in the region.

During the telephone call, Modi also extended his best wishes to US Vice President-elect Kamala Harris, the daughter of an Indian immigrant whose election to the second highest public office in the United States has been cheered in India.

The two leaders also discussed their priorities, including containing the novel coronavirus pandemic, promoting access to affordable vaccines and tackling climate change, the foreign ministry said.