U.S. President Barack Obama and his French counterpart Francois Hollande vowed on Saturday to punish the Syrian government for its alleged use of chemical weapons in internal conflict, just before Obama announced his decision to seek congressional approval for military action.

In their phone conversation, the third in a week, the two leaders "agreed that the international community must deliver a resolute message to the Assad regime -- and others who would consider using chemical weapons -- that these crimes are unacceptable and those who violate this international norm will be held accountable by the world."

Obama told Hollande that "after careful deliberation," he has determined that it is in the U.S. national security interest to take "limited" military action against the Syrian government, and that he would seek congressional authorization first, the White House said in a readout of the talks.

The American leader later made a televised statement to that effect, saying "We should have this debate. I respect the views of those who call for caution, particularly as our country emerges from a time of war that I was elected in part to end."

The Obama administration has been seeking a coordinated military action against Syria with Britain and France, but Britain opted out after its parliament killed a government action plan, dealing a severe blow to the Obama administration's momentum on Syria.

In its efforts to build up the case, the White House on Friday released an unclassified U.S. intelligence report, which concluded with "high confidence" that Syrian government forces had used chemical weapons multiple times in the last year, and that the gas attack on Aug. 21 in the suburbs of Damascus, Syria's capital, left at least 1,429 Syrians dead, among them 426 children.

Obama, who set a red line over the chemical weapons use a year ago, has vowed in the past days to hold accountable the Syrian government headed by President Bashar al-Assad.

Hollande said Friday that France would take part in any action on Syria, and the French parliament will convened an emergency meeting next Wednesday to discuss the Syrian crisis.

The White House called France "a valued ally and friend of the United States," saying the two countries will continue to "consult closely" on Syria in the coming days.