Barack Obama has scored a victory in the 2012 US presidential elections to secure a second term as the leader of the world's most powerful country.

President Obama defeated Republican Mitt Romney to remain at his post for another term. He was speaking to his cheering supporters in Chicago, when he said that the best is yet to come for the country.

Obama congratulated Romney and his running mate Paul Ryan for the hotly contested campaign. Obama, who is the first African American president of the US, said in his victory speech to supporters that he will be speaking to Romney in the coming weeks to discuss ways to take the country forward.

He also thanked the voters in the country for coming out to vote in the elections. "Whether you voted for the very first time or waited in line for a very, very long time - by the way we have to fix that - whether you pounded the pavement... or whether you held an Obama sign or a Romney sign you made a difference," he said.

President Obama walked on the stage along with the first lady Michelle Obama and daughters Sasha and Malia to deliver his victory in Chicago, Illinois.