Australia should consider leaving the Pacific Islands Forum (PIF) if it cannot accept the regional body's firm stance on climate change, Kiribati President Anote Tong said Tuesday.

Tong said global warming had left small island nations fighting for their future and there was no room for compromise on the issue at this week's PIF meeting in Papua New Guinea.

Pacific leaders said Monday that upcoming climate talks in Paris are the last chance for the world to reach an agreement that can save their vulnerable island nations.

The leaders of the six smallest members of the Pacific Islands Forum (PIF) said they were among the hardest hit by climate change, and a binding agreement at the so-called COP21 talks in December was crucial.

The rate at which the world is losing its forests has been halved, but an area of woodland the size of South Africa has still been lost since 1990, a UN report said Monday.

Improvement has been seen around the globe, even in the key tropical rainforests of South America and Africa, according to a surprisingly upbeat Forest Resources Assessment (FRA), which is released every five years.

Eight meters long and weighing 25 tonnes, a replica of the so-called Tsar Bomb, the most powerful nuclear bomb ever detonated, has gone on display for the first time in Russia, in the midst of an ongoing standoff with the West over Ukraine.

Tested in 1961 by the Soviet Union, the hydrogen bomb -- also known as the AN602 -- instilled a mix of pride and fear in retired military pilot Nikolay Krylov as he looked at the replica housed at an exhibition center near the Kremlin. 

Youths wearing gorilla costumes and rubber boots grunted and scampered in front of Rwanda's president on Saturday during the ceremonial naming of 24 baby mountain gorillas in the African country, where the critically endangered animals live in volcano-studded forests that are visited by increasing numbers of foreign tourists.

The young gorillas, whose families are closely monitored by trackers and researchers, were in their wild habitat and not at the naming event in Kinigi, a village near the entrance to Rwanda's Volcanoes National Park. But thousands of people, including students, soldiers, villagers and diplomats, gathered there to celebrate the threatened population of mountain gorillas, whose image adorns numerous sculptures in Rwanda as well as a national currency banknote.

The battle against wildfires sweeping across the drought-stricken western United States, mobilizing 30,000 firefighters, could be the costliest on record with $1.23 billion spent so far, officials say.

Last week alone, a record $243 million was spent fighting more than 40 massive wildfires, said Jennifer Jones, spokeswoman for the U.S. Forest Service, most of them in Washington state, which along with Alaska has borne the brunt of the disaster.

Japan's government on Saturday lifted a 4 1/2-year-old evacuation order for the northeastern town of Naraha that had sent all of the town's 7,400 residents away following the disaster at the nearby Fukushima nuclear plant.

Naraha became the first to get the order lifted among seven municipalities forced to empty entirely due to radiation contamination following the massive earthquake and tsunami that sent the plant's reactors into triple meltdowns in March 2011.

Frustrated negotiators enter the final day Friday of a halting round of crunch U.N. talks to forge a workable draft for a climate rescue pact to be inked by the year's end.

Diplomats have lamented the "snail's pace" of this week's haggle in Bonn, accusing one another of rehashing well-rehearsed positions and holding up the real work of line-by-line text bartering.

A NASA satellite launched just seven months ago has lost the use of one of two science instruments, but the space agency said Wednesday that the mission to map global soil moisture will continue.

The radar instrument aboard the Soil Moisture Active Passive satellite stopped transmitting on July 7 due to a problem with a high-power amplifier. An anomaly team was formed at Jet Propulsion Laboratory to determine if normal operation could be restored, NASA said.

Indonesia has unveiled an ambitious new target for reducing carbon emissions, promising to slash its greenhouse gas output by 29 percent by 2030, the government said Wednesday.

The increased commitment by one of the world's largest greenhouse gas emitters will be officially submitted to the United Nations later this month ahead of a major climate change summit in December.