Hollywood star Leonardo DiCaprio has brought star power to the UN summit on climate change on Tuesday, urging leaders to stop treating global warming as "fiction".

The planet will be drowned in love and good intentions from the United Nations today when leaders from around the world gather for a climate summit that will try to give fresh impetus to global negotiations.

The PM has accused Glenn Greenwald of acting against NZ's interest after the US journalist said he'd release details of NZ's spying activities on its allies ahead of UN vote.

International child mortality rates have dropped by half since 1990 but will still fall short of 2015 targets, new data released yesterday by the United Nations shows.

UN Secretary General Ban Ki-Moon has touched down for a two-day visit, but won't be drawn on NZ's chances of securing a seat on the Security Council.

The UN's new leader on Ebola says the fight against the epidemic is a "war" which could take another six months.

Prime Minister John Key is rejecting claims the Government is too soft on Israel and should expel the Israeli Ambassador.

With the UN warning sugar could be ‘the new tobacco’ because of its risks to health through obesity, you might think a diet that cuts it out would get the thumbs up from experts.

Australia's decision to repeal its levy limiting fossil-fuel pollution makes it the first nation to turn back from a market approach to fighting global warming.

Israel has resumed its air campaign against Gaza after Hamas rejected a six-hour truce and fired dozens of rockets over the border.

Social media has become one of the weapons of war. The Israeli army, which has been on Twitter since 2009, now has 286,000 followers.

Washington has warned Israel against any ground invasion of Gaza, as the UN says more than 40 of the 176 dead were children.

Actress Angelina Jolie will visit the asylum seeker detention centre on Nauru in a move likely to put further international pressure on the Australian Government's harsh policies.

The legal escape route for Muhammad Rizalman bin Ismail has not been updated for more than 50 years.

Abu Bakr al-Baghdadi, the self-proclaimed leader of the Islamic State stretching across Iraq and Syria, has promised to lead the conquest of Rome.

This winter was not a good one for farmers in the Fertile Crescent.

"Which NZ will be turning up in New York should our UN bid be successful?" asks Dita De Boni. "Not just NZers, but citizens of other countries too, have a right to know."

A major new report has revealed that the numbers of refugees, asylum-seekers and internally displaced people worldwide has soared to 50 million for the first time since World War II.

India will offload about a quarter of its rice stockpiles and ease restrictions on selling fruit and veggies as a weak monsoon threatens crop output.

The United Nations hasn't seen so much fun in ages.

Ex-Prime Minister Helen Clark says going for a seat on the UN Security Council is part of the responsibility of membership of the UN for countries like NZ.

Prime Minister John Key says he would support Helen Clark making a bid for United Nations Secretary-General if she put up her hand for the job.

Let's call them what they are: junkets, writes Toby Manhire. They might be effective, they might bring in crucial votes, but the whole approach leaves an unpleasant taste in the mouth.

Eleven UN ambassadors are being schmoozed in Queenstown in an attempt to win support for a New Zealand seat on the UN Security Council.