US President Donald Trump today called for UN Security Council sanctions against the nuclear weapons and ballistic missile programmes of North Korea, terming it as a very big problem. "The status quo on North Korea is unacceptable. The (UN Security) Council must be prepared to impose additional sanctions on North Korean nuclear and ballistic missile program," Trump told Ambassadors of countries on the UN Security Council during a working luncheon in the White House. North Korea, he said, "is real threat" to the world. "It is a big world problem," he added. Noting that it has been left unattended for a long time, Trump said it is time to resolve the North Korean problem. "It is now time to solve the problem,\u201d he said. With the US Ambassador to the UN, Nikki Haley, sitting by his side, Trump slammed the UN Security Council for its stand on Syria. The mission of the UN Security Council is to maintain international peace and security, he said, quickly adding that there is much work for this 15-membered body to achieve. He rued that many of the international problems have been unaddressed for far too long. You May Also Want To Watch: "I encourage the security council to come together to take action to counter all of these many threats. On Syria, the Council failed to respond again to the threat of chemical weapons. I am greatly disappointed by that," he said. Trump said for the United Nations to perform these security challenges, big reforms would be required. Noting that there is need to take a close look at the UN budget, he said cost have absolutely gone out of control. "I'm a budget person.but if you do a good job at the United Nations, I would be less concerned about the budget costs," he added. The US, one of the 193 countries in the UN, pays for 22 per cent of the budget and almost 30 per cent of the United Nations peace keeping missions. "This is unfair," he said. "We need the member states to come together to eliminate inefficiencies and bloat," he said. "We need member states to come together to remove inefficiency in work and ensure that no one nation shoulders a disproportionate share of the burden militarily or financially," said the US President. The United Nations, he felt, is an under performer, but has tremendous potential.