(Adds U.S. and Russian comment)
By Michelle Nichols
UNITED NATIONS, Jan 10 (Reuters) - New United Nations Secretary-General Antonio Guterres urged the Security Council on Tuesday to take more action to prevent conflicts instead of just responding to them as he pledged to strengthen the world body's mediation capacity.
"The United Nations was established to prevent war by binding us in a rules-based international order. Today, that order is under grave threat," Guterres said in his first address to the 15-member council since taking office on Jan. 1.
Guterres, a former prime minister of Portugal and former U.N. refugee chief, said 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.
The council has been largely deadlocked on the six-year war in Syria, with Russia and China pitted against the United States, Britain and France. The body has also been split on its approach to other conflicts and crises such as South Sudan and Burundi, with some members citing sovereignty concerns.
"Russia has suggested ... that failure to respect state sovereignty is the main driver of conflict," U.S. Ambassador to the United Nations, Samantha Power, said.
"Even as Russia has used its veto to insulate itself from consequences in this council for trampling on Ukraine's sovereignty," she said, referring to Russia's 2014 annexation of Crimea.
Russian U.N. Ambassador Vitaly Churkin shot back at Power.
"It is a violation of sovereignty by the United States that led to the very dire situation in a number regions of the world, which we now have to tackle," he said, citing countries including Iraq and Libya.
Guterres asked the council to make greater use of Chapter 6 of the U.N. 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 bolster the United Nations' prevention capabilities, which he described as "fragmented." He has created an executive committee to integrate all U.N. arms and appointed a senior official merge U.N. prevention capacities for better action.
"We will launch an initiative to enhance our mediation capacity," he said. "We spend far more time and resources responding to crises rather than preventing them ... We need a whole new approach."
(Reporting by Michelle Nichols; Editing by Tom Brown)