The United Nations said it would send a mission to Khan al-Assal to investigate after the Syrian government accused rebels of using chemical weapons in the attack last month and rebels countered that government forces were responsible, The Guardian newspaper in Britain reported Tuesday in a blog.
Western nations had called for a U.N. investigation into the use of chemical weapons across the country.
A Foreign Ministry official said U.N. Secretary-General Ban Ki-moon had asked for "additional investigations which might allow the U.N. mission to spread all over the Syrian territories," Syria's state-run news agency SANA reported.
The request, SANA said, "contradicts the Syrian request from the U.N. and indicates to the presence of hidden intentions at the states which have sought to add those investigations as this constitutes a violation of the Syrian sovereignty."
Syrian government won't permit such "maneuvers" but still would allow the mission to visit Khan al-Assal as originally outlined.
Ban called on the Syrian government to cooperate with the investigation.
"I appeal to the government of Syria to extend its full cooperation and to allow the mission to proceed," Ban said.
The Syrian Network for Human Rights, based in London, called on the United Nations and the International Criminal Court to investigate, charge and prosecute "all those involved within the various security branches who have acts of torture, murder and rape, which are considered crimes against humanity ... ."
Meanwhile, a video posted on the Internet showed Free Syrian Army founder Colonel Riad al-Asaad recovering in hospital after an apparent assassination attempt last month, The Guardian said.
In the video, he can be seen smiling and making a victory sign. Opposition officials said al-Assad lost a leg in a car bombing in al-Mayadin in eastern Syria.