U.S. dismisses Syria's inspection offer as 'too late' WASHINGTON - The Obama administration dismissed Syria's offer to allow inspectors access to the site of a suspected chemical weapons attack as having come "too late" and declared there was "very little doubt" the government had used poison gas against civilians - a statement that appeared to move the U.S. closer to a military strike in response. On Sunday, Syrian authorities said their government had agreed to allow United Nations inspectors access to the areas near Damascus where the attacks allegedly took place Wednesday. Opposition groups claim hundreds of people were killed, including women and children. The Syrian government has denied that it used chemical weapons. U.N. officials confirmed that its inspection team, already in Syria to investigate previous allegations of chemical weapons use, would begin "on-site fact-finding activities" Monday. The Syrians have "agreed to provide the necessary cooperation," including a "cessation of hostilities" in the area, the U.N. statement said. But a senior administration official, in a written statement given to reporters on condition of anonymity, brushed aside the Syrian offer. "If the Syrian government had nothing to hide and wanted to prove to the world that it had not used chemical weapons in this incident, it would have ceased its attacks on the area and granted immediate access to the U.N. - five days ago," the official said. By now, the government has had many opportunities to destroy evidence, including by shelling the areas, the official noted. A "belated decision by the regime to grant access to the U.N. team is too late to be credible," the statement said. U.S. officials are continuing to assess the facts to determine "how to respond to this indiscriminate use of chemical weapons," the official said. The president has not made a decision to take action. But as you've seen, we think there is little doubt that these attacks were undertaken by the regime," the official said. Despite the assertion of "little doubt," the administration has not presented any evidence of its own that the Syrian government carried out such an attack, instead citing public reports made by others. The dismissal of the Syrian offer of inspections, the assertion of "little doubt" about the use of proscribed weapons and the labeling of the attack as "indiscriminate" all represented a toughening of the U.S. rhetoric. The language seemed to close off potential avenues for avoiding military action and raised the likelihood of a strike against some Syrian targets. The U.S. has several warships in the eastern Mediterranean capable of launching cruise missile attacks. The statement came as President Obama continued to consult with advisors and allies about a potential response to the alleged use of chemical weapons, which Obama previously had said would cross a "red line." On Sunday, Obama spoke with French President Francois Hollande, while Secretary of State John F. Kerry talked with officials from Turkey, Jordan, Saudi Arabia and the United Arab Emirates. The previous day, Obama talked with British Prime Minister David Cameron. Within the administration, advocates of military action say the U.S. needs to use force to bolster an international norm against the use of chemical weapons. According to that argument, if the U.S. and its allies prove unwilling to use force in this case, they will embolden not just the government of Syrian President Bashar Assad, but also Iran, which has become Assad's chief patron. But others argue that a U.S. strike - especially one lacking U.N. support or definitive proof that Syria launched a chemical attack - could further destabilize an already volatile region and raise the specter of a wider war. Obama and his aides want to avoid setting off a cycle of action and retaliation that would draw the U.S. more deeply into the Syrian civil war. And as recently as Friday, the president had suggested the U.S. would need both clear evidence and a U.N. mandate before taking military action. On Sunday, Israeli Prime Minister Benjamin Netanyahu urged a strong response, saying at a weekly Cabinet meeting that "what happened in Syria was a tragedy and a horrible crime." On the other side, Russian officials warned against a rush toward military action, and a Syrian government statement said any American strike would "create a ball of fire that will inflame the Middle East." The Syrian government has blamed the use of poisons on rebels seeking to discredit the government and bring on international retaliation. Representatives of groups fighting the Syrian government have released videotapes and photographs that appear to show victims of a chemical attack. The images, which have not been independently verified, have caused outrage in many parts of the world. Experts have said the images are not conclusive but could be evidence of use of some form of a nerve gas. On Saturday, the aid group Doctors Without Borders said that three hospitals in the Damascus area that it supports reported receiving 3,600 patients "displaying neurotoxic symptoms" in a three-hour period Wednesday. Of those patients, 355 reportedly died, the group said. The patients showed "symptoms including convulsions, excess saliva, pinpoint pupils, blurred vision and respiratory distress," the group said, adding that it could not determine the cause of the symptoms or who was responsible. Opposition activists have alleged that at least three suburbs east of Damascus were bombarded with toxic gas and that a fourth area was targeted. All four areas are heavily contested between Syrian government and rebel forces and have been the targets of shelling and aerial attacks from the military. Experts on chemical weapons have stressed the need for on-site inspection and the collection of samples from the area and from purported victims. They have added that time is of the essence as some of the suspect substances may dissipate in a few days, making detection more difficult. U.N. Secretary-General Ban Ki-moon on Sunday declared the inspection mission the "highest priority" for the international organization's investigators. The 20-member contingent arrived in Damascus this month with a limited mandate to investigate three previous alleged chemical attacks. The agreement to allow them access came Sunday during a meeting in Damascus between Syrian Foreign Minister Walid Moallem and the U.N.'s top disarmament official, Angela Kane, the government said. In a statement, the Syrian foreign minister said his government was ready to cooperate with the U.N. to "expose the false allegations of the terrorist groups accusing the Syrian forces of using chemical weapons." Syrian authorities routinely refer to armed rebels as terrorists. Parsons reported from Washington and McDonnell from Beirut.