"For two years, I tried to re-unite Libyans and restrain foreign interference […] but for health reasons, I can no longer continue with this level of stress," Salame tweeted.
"Therefore I asked the [UN] secretary-general to relieve me of my duties."
The official took the post three years ago in July 2017 and has recently been moderating talks between Libya’s warring sides on economic, political and military levels.
A spokesperson for the Secretary-General Antonio Guterres Stephane Dujarric said that Guterres received Salame’s resignation.
"The secretary-general has always had full confidence in Salame's work and the great efforts he has made to bring peace to Libya," Dujarric said. "[Guterres] will be discussing with Salame the way to ensure a smooth transition so as not to lose any momentum on the gains that have been made."
Salame, a Lebanese professor of international relations and a former culture minister in his country has many times regretted that the international community is not enough cooperating to help find a way out the conflict; especially countries backing one or the other side of Libya’s warring rivals.
On Jan. 19, in a Germany-led peace summit all countries with interests in the conflict - as well as the two warring sides - agreed to respect the disregarded international arms embargo on the North African nation.
But that pledge was broken almost as soon as it was made, with reports showing the United Arab Emirates (UAE), a key Haftar supporter, was sending in military equipment to Haftar's forces in the east of the country.
A chief oil producer, Libya was plunged into chaos for nine years now after a NATO-backed uprising toppled former leader Muammar Gaddafi in 2011.
In April 2019, Khalifa Haftar, a militia commander whose forces control much of eastern Libya, started an assault on the capital, Tripoli, in a bid to overthrow the internationally recognized Government of National Accord (GNA).