Each of the 20 UN missions around the world, with more than 110,000 personnel collectively, faces a task of unprecedented scale and complexity with inadequate resources, Mr. D'Escoto told the General Assembly at a meeting commemorating the 60th anniversary of UN peacekeeping operations.
"The current annual budget for United Nations peacekeeping is approximately $5.6 billion, which represents one half of 1 per cent of global military spending," noted Mr. D'Escoto.
"This mad asymmetry dooms our best intentions," he added.
The Assembly President highlighted the current crisis in the war-torn eastern region of the Democratic Republic of the Congo (DRC) as an example of the difficult responsibility UN blue helmets tackle.
He pointed out that the UN peacekeeping operation in the DRC, known as MONUC, has one peacekeeper for every 10,000 civilians in a conflict zone which has witnessed violence against civilians and a terrifying campaign of sexual attacks against girls and women that may be unprecedented in its scale and brutality.
"The General Assembly has the responsibility to ensure that operations are equipped with the tools needed to fulfil their mandates," said Mr. D'Escoto. "But almost without exception, they are still being sent into harm's way with insufficient resources at their command."
The President recommended that troop-contributing countries become more involved in shaping peacekeeping mandates and "determining resources required to minimize the risk and maximize the chances of success of the operations their troops are committed to."
Peacekeeping has evolved over the last 60 years from its first mission in the Middle East - observing an uneasy cease-fire between the new State of Israel and its neighbours - to become one of the cornerstones of international diplomacy, Deputy Secretary-General Asha-Rose Migiro told the gathering.
"The presence of peacekeepers sends a powerful signal that Member States of the United Nations are working together for solutions in the best spirit of the Organization's Charter," said Ms. Migiro.
She noted that missions have progressed beyond monitoring ceasefires to receive wide-ranging mandates that include helping post-conflict societies rebuild, nurturing democratic governance, protecting civilians, disarming ex-combatants, supervising elections and strengthening institutions.
"The evolution of peacekeeping has not come without cost," she said. "We have seen that peacekeeping will not succeed in building true security if there is no peace to keep."
Ms. Migiro stressed that if there is no political process in place, "we cannot and should not fight a war."
Peacekeepers operate in some of the most austere and challenging environments to protect people at risk, with limited resources and a tiny fraction of global military spending, she told the gathering, underscoring Mr. D'Escoto's message.
"Peacekeepers need our support. They need clear and achievable mandates. They need the political will and material resources of our Member States," said Ms. Migiro while asking the Assembly to be proud of what has been accomplished and pay tribute to the more than 2,500 peacekeepers and personnel who have lost their lives serving the UN.
"Now more than ever, the world needs the blue helmets, and the blue helmets need the world's support."