U.S. President Barack Obama Tuesday secured the backing of key House leaders in his push for military action in Syria.

Obama promised that the proposed strike against Syria will be "limited" and "proportional while meeting?with Congressional leaders at the White House on Tuesday morning.??

"This is a limited, proportional step that will send a clear message, not only to the Assad regime, but also to other countries that may be interested in testing some of these international norms that there are consequences," Obama said at the onset of the White House meeting.

Following the White House meeting, House Speaker John Boehner expressed his support for Obama's decision to?strike Syria,?saying the use of chemical weapons "have to be responded to."

He believed the?U.S. has the capability and capacity to stop Assad's regime and "to warn others around the world that this type of behavior is not going to be tolerated."?

Nancy Pelosi, the House Minority Leader who is also for military action, said she doesn't believe Congress would reject a resolution authorizing military action.

The White House sent Congress a draft resolution on Saturday to authorize a military strike to punish the Syrian government for its alleged use of chemical weapons on Aug. 21 in a Damascus suburb, which an unclassified U.S. intelligence report said killed at least 1,429 people, including 426 children. Obama promised the strike would not involve boots on the ground.?

Secretary of State John Kerry and Secretary of Defense Chuck Hagel traveled to Capitol Hill later in the day for a Senate Foreign Relations Committee hearing on Syria, insisting inaction would undermine U.S. credibility.

"This is not the time for armchair isolationism ... We have spoken up against unspeakable horror. Now we must stand up and act, " Kerry told a Senate Foreign Relations Committee hearing on Syria.

Hagel, who testified after Kerry, said the alleged use of chemical weapons in Syria represents "grave risks" and "serious threats" to the U.S. national security interests and its allies.

"The United States must demonstrate through our actions that the use of chemical weapons is unacceptable," said Hagel, adding that refusing to act would undermine the credibility of other U.S. security commitments, including Obama's commitment to prevent Iran from acquiring nuclear weapons.

"The word of the United States must mean something," said Hagel. "It is vital currency in foreign relations and international and allied commitments."

"In the event Syria imploded, for instance, or in the event there was a threat of a chemical weapons cache falling into the hands of al-Nusra or someone else, and it was clearly in the interests of our allies and all of us -- the British, the French and others -- to prevent those weapons of mass destruction falling into the hands of the worst elements," Kerry said.

Kerry also pledged that Obama has no intention of sending troops to?Syria.

"Whatever prohibition clarifies it to Congress or the American people, there will be no boots on the ground with respect to the civil war," said Kerry.

As the persuasion efforts were mostly limited to the home front, the U.S. side is still facing enormous challenge to gain international backing for the proposed military strike.

UN Secretary-General Ban Ki-moon said on Tuesday "the use of force is lawful only when in exercise of self-defense in accordance with Article 51 of the United Nations Charter and/or when the Security Council approves such action."

Obama has been in constant contact with?leaders of U.S. allies over the past two weeks to discuss potential response to the alleged chemical weapons attack in Syria.