Tarique Rahman has said he is ready to lead Bangladesh with an ambition to “do better” after his party claimed victory in the country’s parliamentary elections.

The 60-year-old leader of the Bangladesh Nationalist Party (BNP) was reported as saying he was prepared to take responsibility for guiding the nation of 170 million people following what the party described as a “sweeping victory” in Thursday’s polls. Official results have yet to be announced.

The United States Department of State was reported to have congratulated Rahman on what it called a “historic” win.

The elections came about a year and a half after a deadly uprising that toppled the government of former prime minister Sheikh Hasina.

Rahman’s emergence marks a significant shift in Bangladesh’s political landscape. He returned to the country in December after spending 17 years in exile in Britain, away from the centre of political developments in Dhaka.

Widely known as Tarique Zia, he is the son of former president Ziaur Rahman, who was assassinated in 1981, and former prime minister Khaleda Zia, who died in December shortly after his return home.

Rahman was reported as saying that his focus would be on strengthening the country and building on the political changes that followed the end of the previous administration.