Chemical-weapons inspectors have not yet been granted access to the site of a suspected gas attack in the Syrian town of Douma, the head of the global chemical-weapons watchdog said.
"The team has not yet deployed to Douma," Ahmet Uzumcu, director-general of the Organization for the Prohibition of Chemical Weapons (OPCW), said on April 16.
Uzumcu told an emergency meeting of the organization in The Hague that Russian and Syrian officials have informed the OPCW team that there were "still pending security issues to be worked out before any deployment could take place."
The suspected attack in Douma, outside Damascus, in which the World Health Organization has said 43 people who died suffered "symptoms consistent with exposure to highly toxic chemicals," occurred on April 7.
The United States, Britain, and France launched air strikes against Syrian government facilities on April 14 in response.
OPCW inspectors arrived in Syria over the weekend to establish whether chemical weapons had been used in Douma.
The U.S. ambassador to the OPCW, Ken Ward, said that the Russians may have already visited the site of the alleged poison-gas attack, and expressed concern that "they may have tampered with it with the intent of thwarting the efforts of the OPCW fact-finding mission."
The British delegation to the organization called for the inspectors to be given "unfettered access" to Douma, adding that “Russia and Syria must cooperate."
Russia -- Syrian President Bashar al-Assad's main military backer -- denied interfering with evidence at the site of the suspected chemical attack and said the OPCW experts were expected to travel to Douma on April 18.
"Tomorrow the security services of the United Nations...will test the routes. And on Wednesday [April 18] is when we plan the arrival of the OPCW experts," Russian Defense Ministry official Igor Kirillov later said at a news conference in The Hague.
Earlier in the day, Kremlin spokesman Dmitry Peskov rejected Western allegations against Russia as "groundless," asserting that Moscow has consistently supported an "objective" investigation into the suspected gas attack.
Peskov called the U.S.-led air strikes a "violation of international law" and an act of aggression.
Russian Deputy Foreign Minister Sergei Ryabkov earlier suggested that the inspectors' visit to the site had been delayed as a result of the Western air strikes.
Separately, Foreign Minister Sergei Lavrov told the BBC, "I can guarantee that Russia has not tampered with the site."
Lavrov also repeated Russia's claim that there was no chemical attack in Douma, asserting that "what did take place was...staged."
Witnesses and Western governments said helicopters dropped sarin and chlorine bombs that killed many children and women who were sheltering from the fighting between rebels and government troops.
The United States, Britain, and France launched more than 100 missiles, targeting three alleged chemical-weapons facilities on April 14.
The United States and its allies have said the aim of the strikes was to prevent the further use of chemical weapons, not to turn the tide of the war in Syria or topple Assad.
British Foreign Secretary Boris Johnson reinforced this point on April 16 as he arrived at a meeting of EU foreign ministers in Luxembourg.
"I'm afraid the Syrian war will go on in its horrible, miserable way. But it was the world saying that we've had enough of the use of chemical weapons. The erosion of that taboo that has been in place for a hundred years has gone too far under Bashar al-Assad and it was time that we said 'no' and it was totally, therefore, the right thing to do."
A statement adopted by the 28 EU foreign ministers at the meeting said, "We strongly condemn the continued and repeated use of chemical weapons by the regime in Syria, including the latest attack in Douma, which is a grave breach of international law and an affront to human decency."
"The targeted U.S., French, and U.K. air strikes on chemical-weapons facilities in Syria were specific measures having been taken with the sole objective to prevent the further use of chemical weapons and chemical substances as weapons by the Syrian regime to kill its own people," it said.
Referring to economic sanctions, it said that "the European Union will continue to consider further restrictive measures against Syria as long as the repression continues."
The ministers gave no indication that the EU would join the United States, which is expected to announce new targeted sanctions against Russia over its support for Assad.
U.S. Ambassador to the United Nations Nikki Haley said on April 15 that Treasury Secretary Steven Mnuchin would announce the new sanctions on April 16.
But the White House said that a decision on new sanctions had not been made yet.
"We are considering additional sanctions on Russia, and a decision will be made in the near future," White House spokeswoman Sarah Sanders said on April 16.