TEHRAN (Iran News) – The United Nations Secretary-General Antonio Guterres has appealed to Russia and Ukraine to halt fighting as over 200 former UN officials sent a joint letter to the UN chief warning of the world body’s future existence if he does not personally intervene to end the war.

Guterres has called for a four-day “pause” in fighting between Russian and Ukrainian forces during the upcoming Christian Easter Holidays to allow humanitarian aid and evacuations.

Noting that the Easter season is on the horizon amid escalating fighting in eastern Ukraine, the UN chief said the need for a cease-fire is all the more urgent.

“The onslaught and terrible toll on civilians we have seen so far could pale in comparison to the horror that lies ahead. This cannot be allowed to happen,” urging Russians and Ukrainians “to silence the guns and forge a path to safety for so many at immediate risk.”

According to Guterres the goal of the quite limited initiative is to open “humanitarian corridors” for civilians to escape different conflict zones with more humanitarian convoys reaching those areas.

In particular, he referred to the eastern region of Donbass that comprises Donetsk, Luhansk as well as the southeastern city of Mariupol and Kherson in the south.

The Russian military is widely believed to have shifted its focus on Ukraine’s east and southeastern regions.

According to the UN, more than four million people in those areas, and 12 million nationwide, need food, water, and medicine.

Ukrainian Ambassador Sergiy Kyslytsya is said to have called on Moscow to heed Guterres’ call.

The Russian deputy permanent representative to the UN, Dmitry Polyanskiy, has been cited as saying he was “a bit skeptical” about the idea.

“I really don’t know what’s the point of entering in the game with Ukrainians on such issues” report have cited Polyanskiy as saying and maintaining that Russia has already offered to create humanitarian corridors on multiple occasion but Ukraine “didn’t use them or misused them”.

Ukraine has accused Russia of hindering the joint efforts to create such safe routes

Earlier this month, the UN humanitarian chief, Martin Griffiths, traveled to both Ukraine and Russia to try to assess any possibilities for a cease-fire but returned with a pessimistic tone.

On Monday however, Griffiths suggested that there could be what he described as “some ripeness” for a cease-fire as the Orthodox Easter holiday approaches on Sunday.

UN spokesperson, Stephane Dujarric says the world body had already informed the two countries before Guterres went public with his appeal to Moscow and Kyiv noting “we are always hopeful about the prospects for a ceasefire.

This comes as more than 200 former senior UN officials have warned Guterres he risks ending the world body’s very existence, let alone its irrelevance unless the Secretary-General takes a more personal role to mediate a peaceful solution to the Ukraine war.

The former staff members, including many former senior officials such as UN undersecretaries issued the warning to Guterres in a joint letter.

They have urged Guterres to take the lead role in peace talk efforts between the two sides saying this “could include visits to the conflict-stricken areas, discussions with the opposing sides, even moving your own office temporarily to Europe, closer to the urgently needed negotiations and, thereby, indicating the UN’s resolve to address this major crisis head-on.”

The tone of the letter suggests concern by the signatories the UN chief is not living up to his responsibilities.

The letter urges him to be prepared to take personal risks to secure peace, saying the UN is facing “an existential threat”.

“What we and the broader public want to see, though, is a political UN presence and public engagement, in addition to the UN’s notable humanitarian response to the Ukraine crisis,” the authors said.

“We want to see a clear strategy to re-establish peace, starting with a provisional ceasefire, and the use of the UN’s capacity for good offices, mediation, and conflict-resolution.

Critics say there is concern that mediation in Ukraine (where Russia argues it is fighting NATO’s expansion on its border) towards peace has been conducted by actors ranging from different countries instead of an international approach.

This is in stark contrast to the Cuban missile crisis when in 1961, the newly appointed Burmese UN secretary-general, U Thant, played a major role in de-escalating and then mediating the conflict between Russia and the United States.

Likewise, during the buildup to the Persian Gulf war the UN secretary-general, Javier Pérez de Cuéllar convinced the U.S. to negotiate with Iraq.

Prior to the 2003 illegal American invasion of Iraq, the UN also took the task of mediation very seriously and its senior envoy Sergio Vieira de Mello was in the country’s capital Baghdad when an explosion by terrorists at the office of the UN headquarters led to his death.

The authors of the letter include Jeffrey Feltman, UN undersecretary-general for political affairs 2012-2018; Andrew Gilmour, the former UN assistant secretary-general for human rights between 2016 and 19; Franz Baumann, former UN assistant secretary-general for the general assembly until 2015; Ajay Chhibber, assistant secretary-general UNDP; and José Antonio Ocampo a former United Nations undersecretary-general for economic and social affairs.

The signatories have pointed out that “we have decided to raise our voice out of concern for the existential challenge that the United Nations is facing in this historic juncture,”

They write the crisis where Russia on one side and NATO on the other “severely undermines the post-world war two global order. It is the pinnacle of a series of threats to humanity’s peace and security, shared prosperity, and respect for human rights that the UN embodies.”

Defenders of the UN Secretary-General argue that Guterres has been paralyzed in taking any effective measures because of the scale of division between the permanent members of the UN security council, as well as by votes in the general assembly that have revealed deep splits.

The authors of the letter do acknowledge they are not aware of any behind-the-scenes mediation that Guterres may be involved in.

“We know that you care deeply about ensuring a positive impact of our United Nations on humanity and the planet, which will also mark your legacy at the helm of the world body,” they write.

“We, therefore, implore you to intensify your personal efforts, deploying all capabilities at your disposal and acting upon lessons learnt from previous conflicts, for the cessation of hostilities and conflict resolution through peaceful means,”

“This is the raison d’être of the United Nations, which is being tested again in this case. We are horrified at the alternative, the UN becoming increasingly irrelevant and, eventually, succumbing to the fate of its predecessor, the League of Nations, with the human losses and material destruction that went with it.” the letter concludes.

There has also been some criticism of the signatories of the letter itself, as they cite one of the risks to the UN’s decline is because Russia is a permanent member of the UN Securtity-Council with veto power.

Analysts say similar concern was not expressed when another permanent member of the UN Security Member with veto power, the U.S. invaded other countries.

Nevertheless, more than 200 former UN officials conveying such a warning to the Secretary General himself is another example of the many issues which experts say the United Nations itself faces