The Pentagon has said that ISIS leader Abu Bakr al-Baghdadi is still alive, despite repeated efforts by the US-led coalition to kill the terrorist group’s leader.

“We do think Baghdadi is alive and is still leading ISIL (ISIS) and we are obviously doing everything we can to track his movements,” Pentagon spokesman Peter Cook told CNN.

"If we get the opportunity, we certainly would take advantage of any opportunity to deliver him the justice he deserves," he said.

"We're doing everything we can. This is something we're spending a lot of time on."

Cook, however, suggested that Pentagon believes Baghdadi is isolated because the raids have killed many ISIS leaders.

"He's having a hard time finding advisers and confidants to speak with because a lot of them are no longer with us," he said.

The United States, in mid-December, more than doubled the bounty on the ISIS leader’s head to $25 million.

The terrorist group released a video of Baghdadi in 2014, showing a man with a black and grey beard wearing a black robe and matching turban.

Iraqi government documents suggest that Baghdadi was born in Samarra in 1971. He joined the militant group that emerged after the 2003 US-led invasion of Iraq and spent time in an American military prison.