President Obama gives his vision of US leadership to UN

President Barack Obama is addressing the United Nations and laying out a broad vision of American leadership in a changing world, the BBC reported. 

His sixth address to the UN General Assembly was expected to be dominated by US efforts to defeat Islamic State militants in Iraq and Syria.

Officials said he would give a forceful and optimistic message of leadership.

Opening the debate, UN Secretary General Ban Ki-Moon warned that human rights were "under attack."

"From barrel bombs to beheadings, from the deliberate starvation of civilians to the assault on hospitals, UN shelters and aid convoys, human rights and the rule of law are under attack," he told the 193 nations represented.

In the first address to the assembly on Wednesday, Brazilian President Dilma Rousseff focused on the world's economy and the recent economic crisis.

"It is vital and urgent to restore the dynamism of the global economy, which should work towards fostering investment, international trade and the reduction of inequalities among countries," she said.

The US president followed the Brazilian premier and addressed the issues of conflict in Ukraine and Ebola.

Mr Obama's speech marks a turning point in his presidency which had been focused on ending conflicts in Iraq and Afghanistan.

Instead, he outlined America's role as the lead player in a coalition of more than 50 countries committed to defeating Islamic State militants.

The US has carried out a number of airstrikes against the militants in Iraq since August.