Taking a stand against US intervention in Syria, Madonna posted a handwritten note to her Facebook and Instagram pages on Thursday.
The popstar wrote: “US stay out of Syria! For fuck’s humanity’s sake.”
In less than 36 hours, Madonna’s Facebook post received about 10,000 shares, 65,000 likes and more than 2,900 comments. Her Instagram post received more than 32,200 likes.
Also making waves on social media is actress Alyssa Milano, whose fake sex tape has further drawn the public’s attention to the Syria issue.
The video begins as a typical leaked personal movie, but before showing anything explicit, the camera swings around to show a news programme outlining the history of the crisis in Syria.
The video was released on Tuesday on the comedy website funnyordie.com, and has already garnered 3.9 million views.
Milano also used her Twitter page to share information on how people can donate funds to help the children of Syria through UNICEF.
The US government is currently debating military intervention in Syria.
Obama is seeking backing from Congress for military action, putting back the timetable for Syria strikes which had been anticipated even before the two day G20 summit got under way on Thursday.
The two-and-a-half year conflict between Assad and rebels, which began as a popular uprising, has left more than 100,000 people dead.
According to US intelligence, more than 1,400 people living in rebel-held suburbs of Damascus were killed in the August 21 chemical weapons attack, which involved the use of sarin nerve gas.
The US says the Assad regime was responsible, a claim not accepted by Russia.
About a third of Syria's pre-war population of 20.8 million have fled abroad or have been forced from their homes, according to the UN refugee agency.