The Group of Eight held exclusive meetings throughout the day at the main venue in Toyako, northern Japan, as leading emerging economies such as China and India gathered separately in the city of Sapporo.

Oil prices have hit record highs, roiling world economies, while rising food costs have triggered shortages and social unrest in Africa, South Asia and elsewhere. UN-led talks on a new climate pact, meanwhile, have stalled amid myriad disagreements.

Early in the day, US President George W. Bush and German Chancellor Angela Merkel pledged to keep working together, but progress appeared slow on a climate change consensus at the summit, characterised by a split on the issue between Europe and the US. Divisions pitted older, more established economies like those in the Group of Eight with fast rising economies like China and India.

“I’m very satisfied with the work that has gone on on the G8 documents, as regards progress on the issue of climate change, cooperation in the area of food and oil,” Merkel said after a bilateral meeting with Bush.

Bush was more terse after the meeting, not mentioning global warming but telling reporters: “We talked about a lot of common problems, and a lot of common opportunities. We talked about the need to work—continue to work together on Iran.”

On Wednesday, the leaders of these countries will be joined by eight other big-polluting “major economy” nations that are not members, including China and India, to see if a wider agreement is possible.

The G8 nations also said on Tuesday they were deeply concerned that a steep rise in global food prices was threatening food security, which could push millions more people back into poverty. The group also called for countries with sufficient food stocks to make available a part of their surplus for countries in need, in times of significantly increasing prices and in a way not to distort trade. The summit partners appeared close to a deal for using international food reserves to help the poorest countries cope with soaring grain prices.

The G8 also agreed to seek UN sanctions against Zimbabwe, according to Italian Prime Minister Silvio Berlusconi. The need and the urgency was indicated for sanctions at the UN Security Council, Berlusconi said. “Given that even Russia decided to go ahead, it seemed to me important to join in, voting unanimously.” said Berlusconi.

Meanwhile, Russian President Dmitry Medvedev said on Tuesday that his first meeting with President Bush since taking office brought no progress toward bridging deep disagreements between the former Cold War foes.

Deeply wary of creeping Western clout in former Soviet republics and satellite states, Russia adamantly opposes the Bush administration’s plans to deploy missile defense installations in Central Europe and its support for bids by Georgia and Ukraine to join NATO.

Medvedev said on Tuesday that some of the countries’ interests coincide.

On their differences, however, “there is no particular progress,” he said, following Monday’s meeting on the sidelines of the Group of Eight economic powers summit. “We continue to exchange opinions.”