Belgium has defended its decision to allow Zimbabwe's "banned" trade minister to attend a European Union summit in Brussels.

Samuel Mumbengegwi, the Harare minister for trade and industry, arrived on Thursday to attend Friday's Europe-African, Caribbean and Pacific (ACP) council of ministers.

His presence follows February's row between Europe's ministers over the renewal of EU sanctions targeting Robert Mugabe's regime.

Both the European Commission and the Belgian government say the gathering is exempted because the travel bans on Zimbabwean ministers apply only to EU events while the ACP is covered by other international treaties.

Belgium's foreign affairs ministry said that its decision to grant the banned minister a visa to attend the conference was a diplomatic requirement and "absolutely not political".

"We find ourselves under an obligation in international law to allow [the ACP] to invite representatives of their member states," he said. "It is absolutely not a political case."

Justifying Mumbengegwi's entry for the conference, the spokesman hinted that the minister may have been barred if the choice was Belgium's alone.

"It is not a Belgian issue," he said.

"It is like when the UN are allowed to invite someone to address the general assembly, some of these people are not considered a friend of the US but there is an agreement and the situation is similar here."

The European Commission also stressed that it hands are tied by a sanctions agreement signed by EU ministers in February.

"The sanctions and legal obligations have been agreed by Council, they might not be perfect but as long as member states continue to support the agreement it remains," a spokesman said.

British MEP Geoffrey Van Orden disputed the claims."The ACP is just an EU creation, a conduit for the EU's own aid programmes. So we have the ludicrous situation of an individual banned by the EU, coming to the EU's 'capital', with the host country claiming it has no power to stop this," he said.

"The simple fact is that if EU Governments wanted to prevent Mugabe's henchmen from attending meetings in the EU, they would."