The United Nations Support Mission in Libya (UNSMIL) said on its website on Monday that it was following the clashes in and around Tripoli with grave concern, calling on all parties to immediately cease all military action.

"UNSMIL is concerned by the use of indiscriminate fire and heavy weapons in densely populated residential areas, endangering civilian lives and reminds all parties of their duty to protect civilians, in accordance with international humanitarian and human rights law." The UNSMIL said.

It also stressed that political aims must not be pursued through violence and warned that the build-up of armed groups and hostile acts as well as rhetoric risk a wider military confrontation.

"UNSMIL reaffirms its support to the Government of National Accord and calls for serious efforts by all sides to unify the institutions of the country. The Mission stands ready to support all efforts to de-escalate the situation and offers the use of its good offices for this purpose." The statement reads.

The European Union also called for ceasefire and end of hostilities in Tripoli.

"We are following closely the surprising violence that erupted in Tripoli and we call on all parties to restore calm as there is no military solution to the crisis." Bawabat Al-Wasat reported the spokesman for the EU as saying.

Likewise, the Italian Embassy in Libya condemned the violence on Twitter.

"We stand by the people of Tripoli as they face renewed violence in the streets of their beautiful capital. Our condolences go to the victims families, our wishes of prompt recovery to all those injured. Only dialogue can bring peace and reconciliation in Libya, not military action." It said.

The British ambassador to Libya, Frank Baker, also weighed in on Twitter: "Very concerned by the clashes in Tripoli. We call on all parties to cease military action, protect civilians, respect international law and engage in dialogue to de-escalate the situation Libya."

Several have been killed and injured as clashes erupted Monday morning in southern Tripoli.

The Health Ministry reported on Facebook that five have been registered as killed and 33 injured so far due to the clashes.