An Egyptian court has renewed the detention of a Lebanese woman for a further 15 days pending an investigation into charges including insulting Egyptians.

Sunday's court decision comes days after the country's top prosecutor ordered the detention of Mona el-Mazbouh after she posted a video on Facebook lashing out at the state for the prevalence of widespread begging and unchallenged sexual harassment.

In the video, el-Mazbouh talks about her vacation in Cairo where she says she was sexually harassed. She calls Egyptians the "dirtiest people on earth" and Egypt "the country of pimps ... the country of beggars."

She later posted an apology video, saying "I definitely didn't mean to offend all Egyptians."

Police arrested el-Mazbouh on Tuesday before her departure from a Cairo airport.