New York, May 29 (RHC)-- During a major foreign policy speech on Wednesday, U.S. President Barack Obama said Washington would continue to use military force unilaterally "when our core interests demand it."

On the Syrian conflict, Obama promised to work with Congress to increase America's support for the foreign-backed insurgents fighting against the Syrian government. Obama's announcement came amid reports that Washington plans to start training militants in a secret base in Qatar to attack Syrian government troops and vehicles.

Speaking to graduates from the United States Military Academy at West Point, New York, the U-S- president also defended the Pentagon's deadly drone strikes in several countries including Afghanistan, Pakistan and Yemen. International reports show that U.S. drone strikes abroad mainly lead to huge civilian casualties.

Commenting on Iran's nuclear energy program, Obama reiterated that Washington reserves all options to -- in his words -- "prevent Iran from obtaining a nuclear weapon," referring to the war option.

The president's speech came one day after he outlined plans to wind down America's longest running war in Afghanistan by the end of 2016. The plan calls for keeping 9,800 troops in Afghanistan for training and counter-terrorism even after combat missions end later this year.