The world's newest country made its debut before the U.N. General Assembly, warning it is in dire need of help.
South Sudan President Salva Kiir addressed the U.N. body for the first time Friday, saying his country's “march out of the abyss of poverty” will take time, since there is little or no infrastructure.
Mr. Kiir also called for a speedy resolution on border issues with Sudan and for a final agreement on oil.
South Sudan voted to split from the north in a January referendum and officially marked its independence this past July.
Japan's new prime minister also made his debut Friday before the U.N. General Assembly .
Yoshihiko Noda said Japan remains focused on rebuilding after the March earthquake and tsunami that devastated the country, and warned the world's economies must not be deterred by the current economic uncertainty.
Mr. Noda also called for North Korea to take positive steps to resolve concerns about its nuclear program.
Sri Lankan Prime Minister Mahinda Rajapaksa also addressed the world body, saying his country has made progress resettling displaced people following its long war with Tamil rebels.
Mr. Rajapaksa said 95 percent of those displaced by the fighting have been resettled and that Northern province, which saw heavy fighting, has seen its economy grow more than 20 percent.
Sri Lanka's nearly three-decade long civil war ended in May 2009 with the defeat of the Tamil Tiger rebels.
The United States and other countries have been pressing Sri Lanka to carry out a credible and independent probe into alleged war crimes committed during the war. Sri Lanka denies any wrongdoing and has initiated its own investigation into the civil war.