Syria's government warned the U.N. Security Council that delivering humanitarian aid across its borders into rebel-held areas without its consent would amount to an attack, suggesting it would have the right to retaliate against convoys.

As the veto-wielding members of the council — the United States, Britain, France, China and Russia — negotiate a draft resolution to boost aid access, Syria circulated to the 15-member council a letter from dozens of Arab and Syrian lawyers.

The June 18 letter, obtained Friday, argues against a bid by Western states for the resolution to be Chapter 7, which would make it legally binding and enforceable with military action or other coercive measures such as sanctions.