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WASHINGTON Aug 21 (Reuters) - The White House expressed alarm on Wednesday about reports of a massive deadly chemical weapons attack by Syrian government forces and called urgently for a United Nations investigation into the incident.
Syria's opposition accused President Bashar al-Assad's loyalists of gassing many hundreds of people - as many as 1,300 according to on report - in what would, if confirmed, be the world's worst chemical weapons attack in decades.
While the White House stopped short of providing confirmation of Wednesday's attack, saying it was working to gather additional information, it demanded that the Syrian government allow a U.N. team already in the country "immediate and unfettered access" to the location of the alleged attack near Damascus.
The White House announced on June 13 that it would send military aid to Syrian rebels, saying Assad's government had crossed a "red line" by using chemical weapons. But Obama has taken a cautious approach on Syria's 2-1/2-year-old civil war, showing little appetite for deeper U.S. intervention.
However, confirmation of Wednesday's attack could increase pressure on the Obama administration.
"The United States is deeply concerned by reports that hundreds of Syrian civilians have been killed in an attack by Syrian government forces, including by the use of chemical weapons, near Damascus earlier today," White House spokesman Josh Earnest said in a statement.
"We are formally requesting that the United Nations urgently investigate this new allegation. The U.N. investigative team, which is currently in Syria, is prepared to do so, and that is consistent with its purpose and mandate," he said.
Earnest said that "if the Syrian government has nothing to hide," it would facilitate the work of the U.N. inspectors. "They must have immediate access to witnesses and affected individuals, and have the ability to examine and collect physical evidence without any interference or manipulation from the Syrian government," he said.
Syrian Information Minister Omran Zoabi said the allegations were "illogical and fabricated." Assad's officials have said they would never use poison gas against Syrians. The United States and European allies believe Assad's forces have used small amounts of sarin gas in attacks in the past. (Reporting by Matt Spetalnick and Jeff Mason; Editing by Vicki Allen and David Brunnstrom)