"We will keep our promises and honor our commitments," Obama told world leaders at Millennium Development Goals summit.
UNITED NATIONS — The UN General Assembly's annual ministerial meeting opens Thursday with competing speeches by Iranian President Mahmoud Ahmadinejad and President Barack Obama amid efforts to spur negotiations over Iran's suspect nuclear program.
The meeting comes on the heels of a three-day summit to promote the achievement of UN anti-poverty goals by the 2015 target that wrapped up late Wednesday night.
On the sidelines of the summit, European Union foreign policy chief Catherine Ashton, Secretary of State Hillary Rodham Clinton and the foreign ministers of Britain, China, France, Germany and Russia met Wednesday to try to find a solution to the long-running dispute over Iran's nuclear ambitions. They urged Iran to come to the table for a new round of talks, and said it remained essential for Iran to prove its nuclear program is peaceful.
In their meeting on Wednesday, Clinton and the other ministers said they still want to engage with Iran on a fuel swap for its research reactor. They backed the readiness of UN nuclear agency chief, Yukio Amano, to convene a meeting.
"We look forward to Iran's positive and constructive participation in this dialogue," they said.
Obama was scheduled to speak Thursday morning and Ahmadinejad in the afternoon. Others scheduled to address the general assembly included leaders from China, Turkey and Iraq.
On the summit's last day, nations pledged more than $40 billion to battle needless deaths among poor mothers and their children. Leaders exhorted financial donors to fulfill their aid commitments.
"The crisis is no excuse for letting up our efforts, but underscores the need for actions," UN Secretary-General Ban Ki-moon said as he wrapped up the three-day Millennium Development Goals summit.
The United States and Britain said they will continue to do their part to help the global poor.
"We will keep our promises and honor our commitments," Obama told world leaders.
"I suspect that wealthier countries may ask — with our economies struggling, so many people out of work, and so many families barely getting by, why a summit on development?" he said. "The answer is simple. In our global economy, progress in even the poorest countries can advance the prosperity and security of people far beyond their borders, including my fellow Americans."
Along with easing maternal and child mortality, the goals included cutting extreme poverty by half, ensuring universal primary education and halting and reversing the HIV/AIDS pandemic.
The leaders approved a final document saying the UN goals can be achieved and spelling out specific actions to accelerate their implementation over the next five years.