Turkey's prime minister is charging that the Syrian government has used chemical weapons against its people and has called on the U.S. to take stronger action, he told NBC News' Ann Curry in an exclusive interview Thursday.

"It is clear the regime has used chemical weapons and missiles," Turkish premier Recep Tayyip Erdogan said.

Erdogan gave no specifics about when and where the weapons were allegedly used, but he said he believes President Obama's "red line" for the U.S. in deciding whether to take action has been crossed.

"It has been passed long time ago," said Erdogan, who is meeting with Obama on May 16.

"We want the United States to assume more responsibilities and take further steps. And what sort of steps they will take, we are going to talk about this."

Erdogan cited as evidence the "remainders of missiles" — at least 200 by his count — that he believes were used in chemical attacks, along with the injuries of Syrians brought over the Turkish border for medical treatment.

"There are patients who are brought to our hospitals who were wounded by these chemical weapons," he said.

Erdogan rejected any suggestion that the rebels might have used chemical weapons.

"There is no way I can believe in this now. First of all, how are they going to obtain this? And who will give this to them?" he said.

"But if it exists, we are against this...We are against whoever holds the weapons."

A member of the United Nations' commission on Syria claimed this week "strong, concrete suspicions but not yet incontrovertible proof" that the rebels has used sarin gas, but the panel quickly backed away from those claims -- adding that it had "not reached conclusive findings as to the use of chemical weapons in Syria by any parties to the conflict."

The White House — which has said it has varying levels of confidence that sarin was used on a small scale in Syria — quickly threw cold water on the suggestion that the rebels were to blame.

Erdogan said he could not confirm that sarin was used in Syria. "We don't have such a finding yet," he said.

Asked whether Turkey would support a U.S.-enforced no-fly zone in Syria, Erdogan said, "Right from the beginning...we would say 'yes.'"

He denied that Turkey has provided military support to the rebels but said his country has spent nearly $1 billion on aid to 300,000 refugees from Syria.

"We keep the open door policy because they are fleeing oppression." Erdogan said.

Erdogan said he has heard reports that Assad's wife and children have already left Syria, their lives "ruined" by him.

"The thing he should do now is to leave Syria," he said. "Sooner or later, the opposition are going to get him."

Editor's note: An earlier version of this story included a response from Erdogan to a two-part question about whether he would support a U.S.-enforced no-fly zone and American troops in Syria. The translator only asked Erdogan about the no-fly zone, however, and the story has been changed to reflect that.

Amir Cohen / Reuters

Israeli police officers stand near the remains of a rocket fired by Palestinian militants after it landed in the town of Sderot on Thursday.

JERUSALEM - Two rockets exploded in a southern Israeli town near the Gaza border on Thursday, the second day of U.S. President Barack Obama's visit to the Jewish state, Israeli police said.

One of the rockets damaged the yard of an Israeli home but there were no immediate reports of injuries. There were also no immediate claims of responsibility issued in Hamas Islamist-ruled Gaza.

This is a breaking news story - check back for more information 

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Secretary of Defense Leon Panetta on Friday said America is succeeding in Afghanistan, but warned that enemies are looking for new ways to inflict damage.

"In particular, they have sought to take advantage of a series of troubling incidents involving misconduct on the part of American troops," he said in a speech at Fort Benning, Georgia. "These days, it takes only seconds for one picture to suddenly become an international headline."

Panetta addressed about 1,300 soldiers from the 3rd Infrantry Division's 3rd Heavy Brigade Combat Team.

Relations between the U.S. and Afghanistan have been strained by several recent incidents, specifically the burning of Muslim holy books at a U.S. base and the massacre of 17 civilians, including children, allegedly by Staff Sgt. Robert Bales, who is imprisoned at Fort Leavenworth, Kansas, awaiting trial in the killings. In addition, American troops have been videotaped urinating on the bodies of Afghan militants and shown in photographs posing with the body parts of dead insurgents.

"I know these incidents represent a very, very small percentage of the great work that our men and women do every day across the world," Panetta said, "but these incidents concern me — and all of the Service Chiefs — because they show a lack of judgment, a lack of professionalism, and a lack of leadership on the part of some of our men and women in uniform."

“While these are seemingly isolated events by a few bad apples,” Michael Smith, a professor of communications at La Salle University in Pennsylvania told msnbc.com, “they may come to symbolize America to the Afghan population. If this becomes the case, our mission is doomed and the lives of our troops at greater risk.”

Earlier this week, President Barack Obama made a surprise visit to Afghanistan, where he signed an agreement that spells out a winding down of the war as well as a longtime commitment to staying there.

Though no specifics on the number of troops who will remain in an advisory capacity, perhaps for a decade, were announced, the agreement pledges support after 88,000 combat forces leave Afghanistan in 2014 after what will be 13 years of war.

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In the meantime, the United States has said it is committed to stabilizing the Afghan government in the face of a messy insurgency from the Taliban, which hours after Obama’s visit launched a suicide car bomb attack that killed seven people in an a compound housing hundreds of westerners. 

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According to Anthony H. Cordesman of the Center for Strategic and International Studies in Washington and a former Defense Department intelligence assessment director, concerted communications campaigns to build up the images of American troops and the war effort started at the beginning of the Afghan conflict. The campaigns got a whole new emphasis in 2009 when a leaked report by U.S. and NATO commander Gen. Stanley McChrystal bluntly stated that without more forces and a new counterinsurgency strategy in Afghanistan, failure was likely. The report also said the Afghan government was riddled with corruption.

“Similarly, there has been a consistent effort to provide sensitivity and cultural training to U.S. troops, trying to make them aware trying to make them aware how Afghans see the world and Afghan values,” Cordesman said.

In insurgency campaigns — in Afghanistan’s case the Taliban trying to wrest control from the NATO-backed Afghan government — how civilians perceive each side in a conflict is key to cooperation during the war as well as stability afterward, Cordesman pointed out.

“The history, almost regardless of who does this," he said, "is that very often you get the cultural values wrong. You can’t communicate as well as a movement that is local.”

Speaking to the troops is useful, Cordesman said, but it is not a way of having a large impact on what the Afghans think about Americans in the short run. The Quran burning was a particularly egregious episode culturally — it sparked weeks of violent protests — while urinating on bodies and posing with photographs could be viewed as an act of revenge, which Afghans understand, Cordesman said.

While such incidents are damaging, in the end it will be support for the Afghan government that will allow the United States to claim victory in Afghanistan, Cordesman said.

“It’s not support for us that counts,” he said. “It’s support for them that makes transition to any kind of strategic victory possible.”

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