HARARE (Reuters) - Zimbabwean police detained U.S. and British diplomats for several hours on Thursday, slashing the tyres of their cars after they visited victims of political violence ahead of a presidential vote, the U.S. embassy said.

The U.S. ambassador blamed the attack on President Robert Mugabe's government, which it accuses of trying to intimidate opposition leader Morgan Tsvangirai's supporters ahead of the June 27 run-off election.

"Now what they are trying to do is intimidate diplomats from travelling to the countryside to witness the violence being perpetrated against the population," U.S. Ambassador James McGee said in an interview on CNN.

The embassy said the diplomats were released after several hours.

Former colonial power Britain, human rights groups and Zimbabwe's opposition also accuse Mugabe of a campaign of violence to try to keep his 28-year hold on a power. Tsvangirai says 65 people have been killed.

Mugabe blames his opponents for the violence and sanctions imposed by Western countries for the collapse of the once prosperous economy. The opposition says he ruined Zimbabwe.

The attack on the diplomatic convoy took place in Bindura, 80 km (50 miles) north of Harare, the U.S. embassy said.

President of the Japanese International Cooperation Agency (JICA), Madame Sadako Ogata, has commended Malawi for successfully building a strong agricultural base for the country within a few years.

Ogata was speaking to newspersons after meeting Malawi leader Bingu Mutharika who went to attend the Fourth Tokyo International Conference on African Development (TICAD 1V) in Yokohama, Japan.

The Tokyo International Conference on African Development TICAD is a Japanese initiative where African leaders meet development partners to discuss how they can assist them in their development programmes.

Official Malawi News Agency reports that Madame Ogata said Malawi has managed to improve in many areas like infrastructure and agricultural development within a short period time.

She said that on top of infrastructure development, JICA will support Malawi?s efforts in developing agriculture through One Village One Product so that the country can increase its production mainly in rice so that it is able to export to the whole region.

Commenting on the meeting of the two leaders, Ministers of Trade and Industry, and Local Government and Rural Development, Henry Mussa and Dr George Chaponda respectively, who were part of Malawi delegation, said the two leaders discussed three main areas, agriculture (food security), the Shire-Zambezi Water Way Project (Chilomo Bridge) and infrastructure development (Zomba City).

Mussa said Ogata praised Malawi for building a strong agricultural base for the country which has brought food security in Malawi and said the President has asked JICA to increase its support in agriculture because Malawi has shown the world that it is capable of producing enough to feed the whole SADC region given enough resources.

"This time when the world is facing food crisis, Malawi is capable of producing enough rice to export to the whole SADC region given adequate resources in agriculture," said Mussa.

He said currently Malawi produces rice, mainly in Bwanje Valley through the One Village One Product, a project funded by JICA, which it exports to South Africa.

"If we can be supported by our partner organisations like JICA, Malawi can produce rice not only in the Bwanje Valley but also in Karonga, around Lake Chirwa down to Nsanje. During this time when the world is facing global food crisis, we have the advantage to help," he said.

On his part, Minister of Local Government and Rural Development, George Chaponda, said: " Zomba was recently declared a city and we are asking our development partners to assist us with befitting infrastructures so that it improves to the right standard."

The Ministers said Chilomo Bridge is a very important aspect of the Shire-Zambezi Water Way Project, which will serve not only Malawi but the whole SADC region, therefore Malawi asked JICA to assist.

CAPE TOWN (Reuters) - South Africa and Nigeria will forge closer economic ties, easing regulations to boost trade and investment between two of Africa's biggest economies, South African President Thabo Mbeki said on Tuesday.

"The South African government will look at whatever elements in our regulations which might be blocking the intervention and participation of Nigerian companies in South Africa," Mbeki told reporters after meeting with Nigerian President Umaru Yar'Adua.

"We are interested indeed to see more Nigerian companies active in the South African economy."

Yar'Adua is on his first state visit to South Africa.

South Africa has a major presence in Nigeria, with companies such as Standard Bank, MTN and Sasol all active in the oil-rich nation.

Nigeria, the world's eighth-biggest oil producer, became South Africa's largest importer in Africa in 2000 as crude oil imports helped inflate a large South African trade deficit.

According to official data, South African exports to Nigeria totalled 4.8 billion rand in 2007 compared to 12.5 billion rand in mostly oil imports from Nigeria.

"It is our intention that this visit will catapult our relationship into the strategic levels. We must have a strategic partnership between Nigeria and South Africa," Yar'Adua said.