India, March 11 -- The party of Colombian President Gustavo Petro secured a victory in congressional elections, but will have to build coalitions with other parties to carry out announced reforms, including a controversial push to rewrite the nation's constitution. Petro's Historical Pact party won almost a quarter of all seats in the Senate on Sunday and about 15 per cent of seats in the House of Representatives, more than any other party.

But its staunchest opponents also made gains, with the Democratic Centre -- the conservative party led by former President Alvaro Uribe -- securing 17 seats in the 103-member Senate.

Traditional parties, including the Liberals and Conservatives, lost ground in the Senate, while the Green Party also s...