LONDON, UK — United Kingdom Prime Minister David Cameron said on Friday that there is "limited but growing" evidence that chemical weapons were used in Syria.
"It is extremely serious, this is a war crime," Cameron told the BBC. “What President Obama said was absolutely right, that this should form, for the international community, a red line for us to do more.”
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However, Cameron said it was unlikely there would be British troops on the ground in Syria. He emphasized putting pressure on Syrian President Bashar al-Assad's regime, working with the opposition and supporting "people with good motives who want a good outcome."
Britain was among the first western countries to urge international action against the Assad regime. In June 2011 it joined France, Germany and Portugal to bring a resolution before the UN Security Council condemning the regime’s violence against peaceful protestors. Last month, Cameron urged loosening an EU arms embargo against Syria in order to arm the opposition, and said the UK could be willing to act alone if Europe refused.
However Cameron on Friday said he does not want to commit ground troops to Syria, and thought it unlikely that would happen.
“The question is, how do we step up the pressure?” he continued. “We need to shape that opposition . . . so we can bring this to an end.”
The United States has not yet said whether the "red line" has been crossed, stating that its intelligence agencies believe "with varying degrees of confidence" that the nerve agent sarin was used on a "small scale."
On Friday, Obama once again stated that the use of chemical weapons by the Syrian government would be a "game changer."
"Horrific as it is when mortars are being fired on civilians and people are being indiscriminately killed, to use potential weapons of mass destruction on civilian populations crosses another line with respect to international norms and international law," he told reporters at the White House.
"That is going to be a game changer. We have to act prudently. We have to make these assessments deliberately. But I think all of us ... recognize how we cannot stand by and permit the systematic use of weapons like chemical weapons on civilian populations," he said, while meeting with Jordan's King Abdullah in the Oval Office.
A White House official said on Thursday during a briefing on the Syria situation:
We go on to reaffirm that the President has set a clear red line as it relates to the United States that the use of chemical weapons or the transfer of chemical weapons to terrorist groups is a red line that is not acceptable to us, nor should it be to the international community. It's precisely because we take this red line so seriously that we believe there is an obligation to fully investigate any and all evidence of chemical weapons use within Syria.
The official said Washington is urging a comprehensive investigation by the United Nations into the use of chemical weapons, while working with allies and the Syria opposition to procure more information.
So far evidence presented by Western and Israeli officials is not up to the UN proof standards. A team would need, Reuters notes, "to access sites and take soil, blood, urine or tissue samples and examine them in certified laboratories." Samples will be difficult to collect as the Syrian government has refused the UN access, obstructing the mission.
"This is the only basis on which the OPCW would provide a formal assessment of whether chemical weapons have been used," said Michael Luhan, a spokesman for the Organization for the Prohibition of Chemical Weapons (OPCW).
White House spokesman Jay Carney, when asked about the evidence during a Thursday press briefing, repeated the Obama administration's position, saying that the case was not "airtight," and that the US would continue to investigate the matter.
One journalist asked if there was "a concern that [the US] might be showing leniency on the use of weapons of mass destruction?"
"Absolutely not," Carney replied. "The fact is that we do have some evidence, and we do need to build on that. We do have varying degrees of confidence that chemical weapons were used in a limited way."
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Also Thursday, in response to growing concern over Syrian chemical arms use, Turkish Foreign Ministry Spokesman Levent Gumrukcu called recent reports "very alarming." He said he supported a "thorough investigation by the United Nations to substantiate these reports."
However, Gumrukcu noted, "the Syrian regime has not allowed this.”