(CNN) - U.S. Secretary of State John Kerry called a suspected chemical weapons attack in Syria "inexcusable" and "undeniable" on Monday, adding that there was "a clear reason that the world has banned entirely chemical weapons."
He said that evidence "strongly indicates" chemical weapons were used in Syria and that "we know the Syrian regime maintains custody" of such weapons and has the rockets to use them.
Read a transcript of his remarks below.
Well, for the last several days, President Obama and his entire national security team have been reviewing the situation in Syria. And today, I want to provide an update on our efforts as we consider our response to the use of chemical weapons.
What we saw in Syria last week should shock the conscience of the world. It defies any code of morality. Let me be clear: The indiscriminate slaughter of civilians, the killing of women and children and innocent bystanders by chemical weapons is a moral obscenity. By any standard, it is inexcusable and - despite the excuses and equivocations that some have manufactured - it is undeniable.
The meaning of this attack goes beyond the conflict in Syria itself, and that conflict has already brought so much terrible suffering. This is about the large-scale, indiscriminate use of weapons that the civilized world long ago decided must never be used at all, a conviction shared even by countries that agree on little else.
There is a clear reason that the world has banned entirely the use of chemical weapons. There is a reason the international community has set a clear standard and why many countries have taken major steps to eradicate these weapons. There is a reason why President Obama has made it such a priority to stop the proliferation of these weapons and lock them down where they do exist. There is a reason why President Obama has made clear to the Assad regime that this international norm cannot be violated without consequences.
And there is a reason why, no matter what you believe about Syria, all peoples and all nations who believe in the cause of our common humanity must stand up to assure that there is accountability for the use of chemical weapons so that it never happens again.
Last night, after speaking with foreign ministers from around the world about the gravity of this situation, I went back and I watched the videos, the videos that anybody can watch in the social media, and I watched them one more gut-wrenching time. It is really hard to express in words the human suffering that they lay out before us.
As a father, I can't get the image out of my head of a man who held up his dead child, wailing, while chaos swirled around him, the images of entire families dead in their beds without a drop of blood or even a visible wound, bodies contorting in spasms, human suffering that we can never ignore or forget.
Anyone who could claim that an attack of this staggering scale could be contrived or fabricated needs to check their conscience and their own moral compass. What is before us today is real, and it is compelling.
So I also want to underscore that while investigators are gathering additional evidence on the ground, our understanding of what has already happened in Syria is grounded in facts, informed by conscience, and guided by common sense. The reported number of victims, the reported symptoms of those who were killed or injured, the firsthand accounts from humanitarian organizations on the ground, like Doctors Without Borders and the Syria Human Rights Commission, these all strongly indicate that everything these images are already screaming at us is real, that chemical weapons were used in Syria.
Moreover, we know that the Syrian regime maintains custody of these chemical weapons. We know that the Syrian regime has the capacity to do this with rockets. We know that the regime has been determined to clear the opposition from those very places where the attacks took place. And with our own eyes, we have all of us become witnesses.
We have additional information about this attack, and that information is being compiled and reviewed together with our partners, and we will provide that information in the days ahead. Our sense of basic humanity is offended not only by this cowardly crime, but also by the cynical attempt to cover it up.
At every turn, the Syrian regime has failed to cooperate with the U.N. investigation, using it only to stall and to stymie the important effort to bring to light what happened in Damascus in the dead of night. And as Ban Ki-moon said last week, the U.N. investigation will not determine who used these chemical weapons, only whether such weapons were used, a judgment that is already clear to the world.
I spoke on Thursday with Syrian Foreign Minister Muallem, and I made it very clear to him that if the regime, as he argued, had nothing to hide, then their response should be immediate, immediate transparency, immediate access, not shelling. Their response needed to be unrestricted and immediate access. Failure to permit that, I told him, would tell its own story.
Instead, for five days, the Syrian regime refused to allow the U.N. investigators access to the site of the attack that would allegedly exonerate them. Instead, it attacked the area further, shelling it and systemically destroying evidence. That is not the behavior of a government that has nothing to hide. That is not the action of a regime eager to prove to the world that it had not used chemical weapons.
In fact, the regime's belated decision to allow access is too late, and it's too late to be credible. Today's reports of an attack on the U.N. investigators - together with the continued shelling of these very neighborhoods - only further weakens the regime's credibility.
At President Obama's direction, I've spent many hours over the last few days on the phone with foreign ministers and other leaders. The administration is actively consulting with members of Congress, and we will continue to have these conversations in the days ahead. President Obama has also been in close touch with leaders of our key allies, and the president will be making an informed decision about how to respond to this indiscriminate use of chemical weapons.
But make no mistake: President Obama believes there must be accountability for those who would use the world's most heinous weapons against the world's most vulnerable people. Nothing today is more serious, and nothing is receiving more serious scrutiny.