The US is putting pressure on Egypt to repeal its 30-year-old emergency law, which allows detention without charge.
The request was among steps conveyed by US Vice President Joe Biden to Egyptian Vice President Omar Suleiman as a means to resolve the political crisis in the country.
Mr Biden stressed US support 'for an orderly transition in Egypt that is prompt, meaningful, peaceful, and legitimate'.
He also and urged 'immediate, irreversible progress that responds to the aspirations of the Egyptian people'.
Mr Suleiman was quoted on Sunday as suggesting Egypt was not ready for democracy.
A government statement said the emergency law would be lifted 'according to the security conditions' - a phrase giving the authorities wide latitude.
Yesterday saw the biggest anti-government demonstrations so far in Cairo, with hundreds of thousands of people taking to the streets.
UN Secretary-General Ban Ki-Moon said the protestors had to be listened to.