Guterres, 67, was Prime Minister of Portugal from 1995 to 2002, and the UN High Commissioner for Refugees from June 2005 to December 2015. He has become the world's top diplomat on 1 January 2017 and would assume that position for the next five years.
Undoubtedly, Guterres is inheriting several most complicated challenges to peace and security that the world faces, including the war in Syria, Europe migrant crisis, Africa mistrust to UN and climate change.
As per the Article 98 of the UN Charter, the secretary general as head of the UN Secretariat shall act as the chief administrative officer 'in all meetings of the General Assembly, of the Security Council, of the Economic and Social Council and the Trusteeship Council, and shall perform other functions as are entrusted to him by these organs'.
Rules-based International Order
In his first address to the 15-member council since taking office on January 1, Guterres stressed that "the United Nations was established to prevent war by binding us in a rules-based international order."
New United Nations secretary-general has urged the Security Council to take more action to prevent conflicts instead of just responding to them, as he pledged to build the world body's mediation capacity.
He added too many opportunities to prevent conflicts had been lost due to mistrust among states and concerns over national sovereignty.
"Such concerns are understandable, in a world where power is unequal and principles have sometimes been applied selectively. Indeed, prevention should never be used to serve other political goals," he told the council.
"On the contrary, prevention is best served by strong sovereign states, acting for the good of their people," he said.
Guterres also asked the council to make greater use of Chapter 6 of the UN Charter, which allows the body to investigate and recommend procedures to resolve disputes that could eventually endanger international peace and security.
He outlined steps he was taking to build the United Nations' prevention capabilities, which he described as "fragmented".
Sprawling Bureaucracy
On Dec 12, 2016, Guterres was sworn in as Secretary-General of the United Nations, becoming the ninth UN chief in the body’s 71-year history.
Guterres addressed the 193 member nations, saying the world body must work to simplify, decentralize and make more flexible its sprawling bureaucracy, Thehindu.com wrote.
“The United Nations needs to be nimble, efficient and effective. It must focus more on delivery and less on process, more on people and less on bureaucracy.”
Syria Conflict 'Top Priority'
Guterres says he will make ending Syria's civil war his top priority.
"I believe it is the international community's first priority to be able to end this conflict," he told the BBC.
Guterres said the world now faced a dangerous moment, with even countries far from warzones threatened by acts of terrorism.
He called the drive to end armed conflict "a battle for values".
Mideast Crises
Following his election, Guterres had vowed to work as a "convener" and "bridge-builder" to help find solutions to the world's rising challenges.
At the moment, with the political and military vast crises in the Middle East, and the dire situation causing a variety of irreparable consequences to the international community, the role the United Nations can assume to achieve a general consensus among world countries and its rapid reaction against future crises tend to be in the spotlight more than ever.
Europe Migrant Crisis
The Europe migrant crisis and the big wave of the war refugees leaving their homes in the Middle East to find a safe haven in Europe and the terrible conditions these refugees face in the temporary camps they are sheltered in are another problems need to be properly addressed.
It is expected that Guterres by relying on his experiences as a former UN High Commissioner for Refugees find a more efficient solution to the global problem.
Time for Reform
The same helplessness and at times disunity has marked the UN’s response to the civil war that ravaged South Sudan for three years. A US initiative to impose an arms embargo failed, winning only seven votes from the 15 countries that sit on the Security Council.
The approximately 13,000 peacekeepers deployed in the country have been criticized for failing to protect the civilians crowding UN bases.
Elsewhere on the continent, accusations of rape have permanently tarnished the reputation of UN peacekeepers in the Central African Republic.
Guterres has acknowledged the criticism, saying “it is time for the United Nations to recognize its shortcomings and to reform the way it works.”
Presently, however, Guterres needs to do something to overcome the mistrust shaped in the African countries towards the United Nations and its activities there. There are several reports suggesting that some UN aid workers and peacekeepers have abused women and children in exchange for providing them with food and drinking water.
Unfortunately, many such crimes have been left unpunished and the secretary general needs to followed up the cases.
Climate Change Dilemma
Under Ban Ki-moon, representatives of 195 UN member states adopted the Paris agreement within the United Nations Framework Convention on Climate Change.
The major agreement sets out a global action plan to put the world on track to avoid dangerous climate change by limiting global warming to well below 2°C.
According to Guterres, the landmark agreements such as the Paris Climate Agreement “lay out a clear strategy for action.”
Moving forward, the United Nations should focus on “implementation, implementation, implementation,” he stressed.
Guterres put the spotlight on “global mega-trends,” and says it is crucial the international community understands them. “We live in times of multiple, evolving and mutually-reinforcing shifts.”
The dynamics of “geopolitical, demographic, climatic, technological, social and economic nature, enhance threats and opportunities on an unprecedented scale,” he says.
Guterres points out that “climate change affects economies and peoples, their lands, oceans and seas,” identifying it as a source of conflict in the world.