Under pressure from lawmakers for more U.S. backing for Syria's opposition, President Obama on Thursday asked Congress to approve $500 million to equip and train moderate Syrian rebels seeking to remove President Bashar Assad, Reuters reported.

In an effort to assuage concerns that certain equipment given to the Syrian opposition might fall into the hands of U.S. enemies, rebels would be vetted before receiving assistance, a White House statement said, according to the new agency.

The money is less than half of a $1.5 billion plan for a Regional Stabilization Initiative, which also involves neighboring countries Jordan, Lebanon, Turkey and Iraq, and plans to aid the moderate opposition, the Associated Press reported.

Obama has been under pressure from some lawmakers to give more assistance to Assad's moderate opposition in the nation's civil war.

The stabilization plan, “would help defend the Syrian people, stabilize areas under opposition control, facilitate the provision of essential services, counter terrorist threats, and promote conditions for a negotiated settlement,” National Security Council spokeswoman Caitlin Hayden said in a statement, according to Business Week.

“While we continue to believe that there is no military solution to this crisis and that the United States should not put American troops into combat in Syria, this request marks another step toward helping the Syrian people defend themselves against regime attacks, push back against the growing number of extremists like ISIL who find safe haven in the chaos, and take their future into their own hands by enhancing security and stability at local levels,” Hayden said.

Additionally, the Defense Department would extend arms and training to “appropriately vetted elements of the moderate Syrian armed opposition,” she added.

The news was made public on Thursday that the stabilization plan is part of a larger $65.8 billion Overseas Contingency Operations budget, which was submitted to lawmakers on Thursday by the Obama administration. The requests were made on the heels of Obama facing criticism for reserved policies in Syria, which some say has allowed for the Sunni insurgency to gain strength in Iraq, the AP wrote.

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