UNITED NATIONS Britain said Thursday it has sent a letter to Secretary-General Ban Ki-moon with new information on three further incidents of alleged chemical weapons use by the Syrian government.
Britain's U.N. Ambassador Mark Lyall Grant said his government has continued to provide new information to the secretary-general and the head of the U.N. team Ban appointed to investigate alleged chemical weapons attacks in Syria.
CBS News has confirmed that the British government sent the letter as a formal "expression of concern" about three specific incidents of alleged chemical weapons attacks in Syria, CBS News correspondent Margaret Brennan reports.
Those alleged incidents took place March 24, March 25 and April 29, Brennan reports.
The Syrian government asked Ban to investigate an alleged chemical weapons attack by rebels on March 19 on Khan al-Assal village in Aleppo, but insists that any probe be limited to that incident. Syrian soldiers were reportedly killed and injured in the incident, which the rebels blame on Syrian forces.
Ban is insisting on a broader investigation, including a December incident in Homs raised by Britain and France. He appointed Swedish chemical weapons expert Ake Sellstrom to lead a U.N. investigation. Syria has refused to allow his team into the country.
"We continue to inform the secretary-general and Mr. Sellstrom of any information as and when we get it," Lyall Grant told several reporters. "I sent a further notification to the secretary-general last week."
The U.K. Foreign Office added that the letter was meant to draw Ban's attention to the three further allegations of chemical weapons use and ask that those be included in the U.N.'s investigation. Those allegations relate to incidents which reportedly took place in March and April of this year and which have been reported in the media, the Foreign Office added.
"The U.K. is extremely concerned about the ongoing allegations of chemical weapons use in Syria," it said in a statement.
A senior U.N. diplomat said last week that Ban has received new information about alleged chemical weapons incidents since the beginning of April. The diplomat, speaking on condition of anonymity because of the sensitivity of the issue, refused to give any details.
The confirmed use of chemical weapons could escalate the international response to the more than two-year-old conflict, which has killed more than 70,000 people, according to the United Nations.
"Our view is that all the attacks are by the government," Lyall Grant said. "We have no information that the opposition has access, let alone used chemical weapons."
Last week, U.N. Mideast envoy Robert Serry told the Security Council that there were mounting reports of chemical weapons use as violence escalates in Syria. He gave no details but said the secretary-general remains "gravely concerned" about the allegations of chemical weapons use.
In response to the reports, Serry again urged the Syrian government to allow chemical weapons experts into the country immediately to investigate the allegations. While the U.N. team can question people outside Syria and analyze material they obtain, Ban has stressed repeatedly that on-site investigations are essential if the U.N. is to determine whether chemical weapons have been used.
Also Wednesday, Syrian grassroots activists threatened to cut ties with the main exile-based opposition group after it got bogged down in a week of internal power struggles instead of devising a strategy for possible peace talks with President Bashar Assad's regime.
Such talks are to be launched with a U.N.-sponsored international conference in Geneva, tentatively set for next month, though there's no firm date, no agenda and no list of participants.
The latest signs of disarray in the notoriously fractured Syrian opposition raised more troubling questions about the Geneva conference, including who would represent those trying to bring down Assad and what mandate would they have.
A further sticking point arose Wednesday, with Iran, an Assad ally, seemingly angling for an invitation. Iranian Foreign Minister Ali Akbar Salehi said that his government "supports Geneva talks and U.N. efforts."
However, French Foreign Minister Laurent Fabius said the West fears that an Iranian presence would be counterproductive, and that Tehran would try to leverage the Syria crisis to win international acquiescence in its suspected nuclear weapons program.
"As far as we're concerned, our fear is that there would be a merging of the Syrian problem and the Iranian nuclear problem," Fabius told Radio France. "We fear that if they (the Iranians) are present at the conference on Syria, that they could cause delays in a way that a blackmailing situation would arise in which case perhaps they'll say they'll allow a resolution in the Syrian crisis but on condition that we allow them to make nuclear weapons."
Iran insists its nuclear program is strictly for peaceful purposes.
The Syrian regime has said it agrees in principle to attend the Geneva talks, but has not said on what terms.
However, the gaps between Assad and his opponents on Syria's political future remain wide. Assad has said he will remain in office until elections are held in Syria, while the political opposition says his departure from power must top the agenda of any peace talks.
The main political opposition group, the Syrian National Coalition, began meetings a week ago in Istanbul, Turkey, to expand its decision-making bodies, choose a new leader and devise a joint position on the Geneva talks.
Instead, the group has spent most of that time on the membership issues, with rivalries between Qatar and Saudi Arabia over influence apparently playing out in the background.
On Wednesday, the Revolutionary Movement in Syria, an umbrella organization of activist groups from across the country, issued what it called a final warning, threatening to withdraw its backing for the coalition if it doesn't come up with a political strategy.