A statement issued by Ban's spokesman said the special envoy is "to undertake urgent consultations with the authorities in Tripoli and in the region on the immediate humanitarian situation as well as the wider dimensions of the crisis", Xinhua reported.
The north African country has been witnessing riots since Feb 14 when anti-regime protests began against Muammar Gaddafi's 41-year rule.
"The secretary-general is deeply concerned about the fighting in western Libya, which is claiming large numbers of lives and threatens even more carnage in the days ahead," xinhua quoted the spokesman as having said in the statement.
Ban also spoke with Libyan Foreign Minister Musa Kusa "and strongly appealed for an end to the hostilities and for full compliance with (UN) Security Council resolution 1970," the statement said.
The resolution 1970, adopted by the Security Council Feb 26, imposed sanctions on Libya, including an arms embargo against Libya and travel ban and asset freeze directed at Gaddafi and his family members.
In his telephonic conversation with the Libyan foreign minister Sunday, the UN chief called on the authorities in Tripoli "to uphold their responsibility to protect the country's citizens and to heed the Libyan people's legitimate aspirations to live in dignity and peace", the statement said.