Discussions are likely to focus on Mr Blair's recent African tour

President Sampaio's visit was to have taken place in November, but with Mr Blair then shuttling around the world in a bid to bolster what he termed the coalition against terrorism, his aides asked Mr Sampaio to postpone the visit just days before it was due to start.

This "dis-invitation" as it was described in the Portuguese media came just weeks after Mr Blair failed to invite the Portuguese prime minister to a meeting of EU leaders to discuss the security situation, and thus caused some consternation in Portugal.

President Sampaio did not comment publicly and both sides will now be keen to look forward when they meet for talks on Tuesday afternoon, focusing among other things on African issues after Mr Blair's recent tour of the continent.

Defence interest

Following an audience with the Queen on Wednesday, the Portuguese president on Thursday takes the unusual step for a foreign head of state of addressing the Scotland's devolved parliament on the future of Europe.

Having lived in the UK in his youth, Mr Sampaio has a good grasp of British politics and is aware that Scotland is seeking to reposition itself within the EU.

As commander in chief of Portugal's armed forces, Mr Sampaio has a strong interest in defence issues and recently called for an extension to the president's powers in this area.

Looming election

Although his post is largely ceremonial, he has not shrunk from calling for reforms where necessary.

In a recent interview, he repeatedly cited the UK as a good example, for instance contrasting the way a new British government takes office overnight after a general election, compared with a delay of almost a month in Portugal.

It could be longer after the Portuguese general elections scheduled for 17 March.

Mr Sampaio, a socialist, may have to exercise his political judgement in deciding whom to ask to form a government as the election may well not be decisive.