BERLIN (Sapa-AP) - German Chancellor Angela Merkel said Saturday that she hopes African leaders will support tougher sanctions against Zimbabwe when they participate at the upcoming Group of Eight summit.

Leaders including South African President Thabo Mbeki, whom Zimbabwe's opposition has accused of bias toward President Robert Mugabe, and Nigerian President Umaru Yar'Adua have been invited to a meeting as part of the summit in Japan, starting Monday.

Merkel told The Associated Press this week that the European Union would seek "all possible sanctions" against Zimbabwe's government and leader in the wake of its widely denounced presidential election runoff.

She underlined that stance in her weekly video message, in which she looked ahead to the G-8 summit.

"We will confer on how we can toughen sanctions against Zimbabwe, and I hope that we will also get support from our African colleagues here," Merkel said.

A U.S. official also predicted the Group of Eight industrialized nations will take a stand regarding Zimbabwe and its leader.

"I believe it will be part of the G-8 statement," Dennis Wilder, the U.S. National Security Council's senior director for Asian Affairs, told reporters while travelling on Air Force One with U.S. President George W. Bush to Japan on Saturday.

"I think the G-8 will strongly condemn what Mugage has done. It will strongly question the legitimacy of his government and his governing Zimbabwe," Wilder said.

The EU already has travel bans and an asset freeze in place on Mugabe and other senior Zimbabwean officials. However, African Union leaders have failed to deliver a strong unified message over voting widely dismissed as a farce after Tsvangirai pulled out, citing violence and intimidation.

Beyond Zimbabwe, Merkel said that the G-8 and African leaders would discuss "how the industrial countries can help African countries strengthen their own farming sector" in the face of soaring food prices.

She added that they would consider what standards should be applied to growing crops for biofuels "so that no competition with food production worldwide can arise."

Merkel said it was "particularly important" for the world's leading industrial nations to confer with top emerging economies - China, India, Mexico, Brazil and South Africa - in discussing how to tackle high energy prices.

"We will consider to what extent it is possible to stem speculation and bring output into line with demand," she said.