Western condemnation of Robert Mugabe's presidential election victory in Zimbabwe has triggered a split with African nations.

As the UK and US led calls for action, and as the Western chorus of censure was joined by France and Germany, divisions soon emerged as the African view of Mugabe's fifth term victory opened a damaging row - with strong colonial and racial overtones - over plans to extend sanctions on the country.

An Organisation of African Unity observer mission described the elections as "transparent, credible, free and fair".

South Africa - the key regional player - refused to condemn Mugabe insisting that it was as yet too early to judge the result.

South African observers blamed "administrative oversights" and the Nigerians issued a statement claiming that there had been "no incidents sufficient to threaten the integrity and outcome of the election in areas monitored by the team".

The emerging row threatens to split the Commonwealth, whose election mission has yet to report, and will present an obstacle to Britain's intention to press other European countries to take tough action at an EU summit this weekend.

Responding to the result, the foreign secretary Jack Straw said: "For months the government of Zimbabwe has conducted a systematic campaign of violence and intimidation designed to achieve one outcome - power at all costs.

"It is no surprise that this outcome has now been achieved. We will be consulting our friends and allies in the European Union, the United States and the Commonwealth."