DAMASCUS, Syria (AP) — The U.N.'s secretary general is urging the West to hold off on any attack on Syria until U.N. chemical weapons inspectors finish their investigation in the suburbs of Damascus -- the site of last week's alleged chemical weapons attack.

Ban Ki-moon says it should take the inspectors four days to finish their work on site, and then their findings will have to be analyzed.

He says the team has already "gathered valuable samples and interviewed victims and witnesses."

Syrian activists say the U.N. experts have taken biological samples from several victims of last week's purported poison gas attack.