AMERICAN President Barack Obama has admitted that his efforts to help resolve the Syria crisis have so far failed, but defended his strategy and dismissed assertions that Russian President Vladimir Putin is now the dominant world leader.

“I didn’t say it was going to be done in a year,” Obama said in a US 60 Minutes interview. “Syria has been a difficult problem for the entire world community. What we have not been able to do so far — and I’m the first to acknowledge this — is to change the dynamic inside of Syria.”

The president was confronted about several unsuccessful efforts in Syria, ravaged by a four-year-long civil war and now by the Islamic State terror group.

Obama also said he had no knowledge that Hillary Clinton, as his secretary of state, used a private server and email accounts to conduct official business.

He acknowledge that the arrangement resulted in security breaches but said he didn’t think she attempted to hide information and declined to address the question of whether she could be prosecuted under his administration.

Obama also acknowledged that Donald Trump has tapped into voters’ dissatisfaction to lead the Republican presidential field and that he has so far run a dynamic campaign but suggested that Trump wouldn’t win the party nomination.

Still, the biggest questions and answers focused on the Putin and the Middle East, specifically the failed, $AU682 million effort to train and equip a moderate opposition to fight the Islamic State.

The administration ended the program last week, following a report by the US military that efforts to train as many as 5,000 rebels had only done so for about 50 and now only four or five remain.

“There’s no doubt that it did not work,” said Obama, while acknowledging the he was “sceptical” about the plan from the beginning and that he was willing to try several options.

He also said that training Syrians to defeat the Islamic State will be difficult as long as the regime of President Bashar Assad remains in power.

Obama also refused to accept the notion that Putin has challenged his leadership and assertion last year that America is an “indispensable nation.”

“If you think that running your economy into the ground and having to send troops in, in order to prop up your only ally is leadership, then we’ve got a different definition of leadership,” said Obama, referring to Putin’s efforts in Ukraine.

“My definition of leadership would be leading on climate change. … My definition of leadership is mobilising the entire world community to make sure that Iran doesn’t get a nuclear weapon. And with respect to the Middle East, we’ve got a 60-country coalition that isn’t suddenly lining up around Russia’s strategy. To the contrary, they are arguing that, in fact, that strategy will not work.”

This story originally appeared on Fox News.