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President Obama said Saturday the United States should take military action against Syrian President Bashar al-Assad for using chemical weapons on civilians but also turned to Congress for approval -- dealing a potential setback to America's foreign policy and setting up what will likely be a hard-fought Washington debate on the issue.

“This menace must be confronted,” Obama said of the Assad regime’s alleged chemical attack, speaking from the Rose Garden.

However, the announcement also raised the question about whether the president put the burden on Congress to act.

"President Obama is abdicating his responsibility as commander in chief and undermining the authority of future presidents," said New York Rep. Peter King, a member of the House Permanent Select Committee on Intelligence. "The president doesn't need 535 members of Congress to enforce his own red line."

The president was driven to make a decision following an Aug. 21 chemical attack outside Damascus that killed more than 1,400 people, including hundreds of children. The attack was just one of several allegedly carried out by the Assad regime after Obama said about 12 months ago that the regime using a chemical weapon would “cross a red line.”

The decision also sets up a congressional debate that could drag on for weeks, with members of Congress divided about whether the U.S. should get involved in another Middle East conflict.

Georgia Sen. Saxby Chambliss, the top Republican on the Senate Select Committee on Intelligence, said he agreed with the president that the U.S. “must respond” and thanked him for seeking congressional approval. However, he criticized Obama for failing to “present a strategy and objectives for military action” and for not demanding Congress return immediately and debate “this most serious issue.”

Florida Democratic Sen. Bill Nelson, a member of the Senate Armed Services Committee, said the president wants to put to rest any doubts the American people may have.

“I support the president's decision,” Nelson said. “But as far as I’m concerned, we should strike in Syria today. The use of chemical weapons was inhumane, and those responsible should be forced to suffer the consequences.”

They are just two of several members of Congress shaping the debate, which began soon after the start of Syria’s roughly 2-year-long civil war.

On Friday, Utah Republican Sen. Mike Lee suggested the president must first convince him before getting his support.

“He has to demonstrate to me and other members of Congress that this is in the national security interest of the American people, not just that Mr. Assad is a bad guy,” Lee, a Tea Party-backed lawmaker, told Fox News. “We know that.”

Obama, with Navy ships in the Mediterranean Sea ready to strike, said he would wait for Congress to make its scheduled Sept. 9 return from August recess, arguing a military strike is “not time sensitive” and would be effective even one month from now.

The White House sent Congress on Saturday afternoon a draft resolution on taking military action.

The decision to seek congressional authorization is a departure from the administration’s decision to intervene in Libya in 2011. Though the president said he thinks he has the authority to order a military strike, he made clear he will ask Congress to vote on the issue.

“I have decided that the United States should take military action against Syrian regime targets,” the president said. “I’m also mindful that I’m president of the world’s oldest constitutional democracy.”

The administration will now proceed with a series of briefings with lawmakers on Capitol Hill lasting through the weekend -- the Senate on Saturday and the House on Sunday -- as it tries to build a case for military strike.

Obama also indicated he will not wait for either approval from the U.N. Security Council or the conclusion of U.N. inspectors’ investigation into the Syria attack.

A Senate aide told Fox News on Saturday that bringing senators back early is under consideration. And on Friday, a spokesman for House Speaker John Boehner said the congressman has not ruled out such a move.

Senior administration officials said Obama had planned to take military action against Syria without congressional authorization, but told aides Friday night that he had changed his mind.

The officials describe a president overriding all his top national security advisers, who believe consulting with Congress was sufficient.

The officials, who spoke on the condition of anonymity, said Obama spent the week wrestling with Congress' role and made the decision Friday after a lengthy discussion with his chief of staff, Denis McDonough.

The president did not say what he would do should Congress fail to support a strike.

Already this week, British Prime Minister David Cameron suffered a humiliating defeat when the House of Commons refused to support his call for military action against Syria.

The Assad regime has blamed rebels trying to overthrow the government for the Aug. 21 attack and has threatened retaliation if it is attacked.

Russian President Vladimir Putin has urged Obama to reconsider, saying he is trying to appeal to a Nobel Peace laureate rather than a president.

Still, the president’s announcement Saturday brought cheers in the streets of Syria.

The new U.S. timetable will nevertheless give U.N. inspectors time to receive lab results from the samples they took during four days in Damascus and to compile a final report. After leaving Syria overnight, the inspection team arrived in Rotterdam a few hours before Obama spoke.

The group's leader was expected to brief Secretary-General Ban Ki-moon on Sunday. U.N. spokesman Martin Nesirky said Saturday “whatever can be done will be done” to speed up the process but offered no timetable for releasing findings on whether chemical weapons had been used last week.

On Saturday, other Republicans also generally expressed satisfaction at Obama's decision but challenged him to make his case to the public and lawmakers alike.

"We are glad the president is seeking authorization for any military action in Syria in response to serious, substantive questions being raised," Boehner, R-Ohio, and other House Republican leaders said in a joint statement.

Obama repeated Saturday that he was considering limited and narrow steps to punish Assad, adding that U.S. national security interests were at stake. He pledged no U.S. combat troops on the ground in Syria, where the civil war has claimed more than 100,000 civilian lives.

In the hours before Obama's Rose Garden announcement, he was joined at the White House by top advisers including Vice President Joseph Biden, Defense Secretary Chuck Hagel and Secretary of State John Kerry.

Polls suggest winning public support will be an uphill climb. A new Reuters’ poll shows U.S. support for intervention has increased over the past week to 20 percent, up from just 9 percent, with more than half of Americans opposing intervention.

Kerry indicated Friday that the administration will try to convince the public and Congress that America has an 'obligation' to act.

“The president asked all of us on his national security team to consult with the leaders of Congress as well,” Kerry said. “I will tell you that as someone who spent nearly three decades in the United States Congress, I know that consultation is the right way for a president to approach a decision of when and how and if to use military force.”

The Associated Press contributed to this report.