BEIRUT (AP) -- There's no apparent letup today in the Syrian government's military assault on the rebellious city of Homs.

Activists say scores of people have been killed today, as government forces continue to bombard neighborhoods with mortars and rockets. During lulls in the shelling, residents have been using loudspeakers to call for blood donations and medical supplies.

President Bashar Assad's crackdown on the increasingly militarized opposition has left his regime almost completely isolated internationally, and sanctions are crippling Syria's economy.

A senior Arab League official says the organization will discuss at a meeting Sunday whether to recognize the opposition Syrian National Council as the country's legitimate representative.

But Assad has received political backing from Russia and China. The two countries blocked a U.N. resolution over the weekend that called for Assad to leave power.

Since the uprising began in March, the U.N. estimates more than 5,400 people have been killed. That count does not include the hundreds believed to have been killed since Saturday, when the government launched its latest offensive against Homs.