WASHINGTON -- Secretary of State John Kerry said Friday that the U.S. has evidence the Syrian government used chemical weapons against its own people, as the White House released a four-page report summarizing their case against the Bashar Assad regime.

President Obama has not made a final determination on whether the U.S. will carry out a retaliatory military strike against Syria, but a senior defense official told USA TODAY that the military leaders are preparing for a strike that would be "limited" to a number of targets and short in duration.

The U.S. military is ready to execute a strike immediately on the president's order, said the official.

Kerry said the administration is releasing an intelligence report today laying out their evidence. Proving this allegation is considered a threshold that the U.S. would use to justify a potential military strike on that country.

"I'm not asking you to take my word for it," Kerry said. "Read for yourselves the verdict reached by our intelligence community" that the government of Syria was responsible for the attack.

The intelligence community believes with "high confidence" that Assad government used chemical weapons in Damascus suburbs based on human sources as well as intercepts of conversations by senior Syrian officials, according to the report and Kerry. Assad is the ultimate decision maker for the chemical weapons program, according to the report.

The Syrian regime has the types of munitions were used to carry out the attack on August 21, that left more than 1,400 dead, according to the report. The regime also has the ability to strike simultaneously in multiple locations.

The U.S. intelligence community has discounted the possibility that Syrian rebel groups could have behind the attack, noting that it doesn't have rocket and artillery capability that was used in the most recent attack.

"We assess that the Syrian regime has used chemical weapons over the last year primarily to gain the upper hand or break a stalemate in areas where it has struggled to seize and hold strategically valuable territory," the report said. "In this regard, we continue to judge that the Syrian regime views chemical weapons as one of many tools in its arsenal, including air power and ballistic missiles, which they indiscriminately use against the opposition."

With the release of the intelligence report and a telephone briefing for lawmakers on Thursday evening, the White House looked to bolster the case for taking action against Assad even as objections to a strike continue to mount in the U.S. and with the nation's closest ally, Britain, to taking military action.

Obama was also given a bolt of international backing on Friday, when President Fran├žois Hollande of France announced his support for international military action against the Syrian government.

On Thursday, the British parliament voted to reject taking military action in Syria, even the government published an intelligence document that detailed how it concluded the Syrian government was responsible for the chemical attacks on the outskirts of Damascus last week.

Obama still has not on announced whether he will take action against the Syrian regime, but Kerry's rhetoric seemed to underscore that military action will be forthcoming.

"The primary question is no longer what do we know," Kerry said. "It is what are we in the world going to do about it?"