Ban Ki-moon urged the Security Council to act quickly on a proposed package of UN sanctions to force the Libyan President Muammar Gaddafi to end its violent crackdown on people, the UN News Center reported.
"It is time for the Security Council to consider concrete action," he told the council, noting, "The hours and the days ahead will be decisive for Libyans."
He said that the situation in Libya is deteriorating, adding that the people's will must prevail.
Elsewhere in his remarks, Ban said there have been reports of mercenaries attacking foreigners in Libya.
He went on to say that "clear and egregious" violations of human rights have taken place in Libya, underlining that over 1,000 people have died in the unrest so far.
The UN chief also recommended that Tripoli be suspended from the Human Rights Council.
Ban is scheduled to hold talks on the situation in Libya with US President Barack Obama on Monday.
Earlier on the day, European Union states agreed to impose an arms embargo on Libya, freeze the assets of Libyan officials and consider imposing a travel ban on members of the Tripoli regime.
Earlier on Wednesday, UN High Commissioner for Human Rights Navi Pillay said a no-fly zone may be imposed on Libya to protect the lives of protesters from the airstrikes.
Over one thousand people have been killed and more deaths are feared as Gaddafi is brutally crushing the revolt.