Indian Prime Minister Narendra Modi congratulated Tshering Tobgay on winning Bhutan's national election.
Tobgay was the prime minister of Bhutan from 2013 to 2018. His party, the PDP, won 30 of the 47 seats, while the Bhutan Tendrel Party (BTP) secured 17 seats.
"Heartiest congratulations to my friend Tshering Tobgay and the People's Democratic Party for winning the parliamentary elections in Bhutan", Modi said in a tweet on late Tuesday night.
"Look forward to working together again further to strengthen our unique ties of friendship and cooperation", Modi added.
Tobgay is regarded as pro-India, and during his tenure, India had good relations with the neighbouring country.
Tobgay, 58, a former bureaucrat who completed his master's at Harvard, was the first leader of the opposition in Bhutan's first parliament when it was established in 2008 after the end of the king's reign.
In his party manifesto, he attacked the ruling government, citing statistics showing that one in every eight people were struggling to meet their basic needs for food and other necessities.