The trip is officially being billed as an opportunity to discuss bilateral relations.

Last week, in his weekly television show in Caracas, the Venezuelan capital, Chavez said that he was ready to let "bygones be bygones", but also joked that the king ought to know it is not in his nature to sit quietly.

Chavez said: "I would very much like to give the king a hug. But you know, Juan Carlos, that I am not going to shut up."

Awkward exchange

The argument with Juan Carlos occurred at a summit in the Chilean capital Santiago in November, when the Venezuelan leader repeatedly referred to Jose Maria Aznar, the former Spanish prime minister, as a fascist while seated in a panel next to the king and Zapatero.

After being warned repeatedly by both Juan Carlos and Zapatero to tone down his rhetoric, the king snapped: "Why don't you shut up?"

The exchange quickly made its way into news broadcasts and onto the internet, and was even marketed as a mobile phone ring tone in Spain.

Chavez demanded an apology, and said he was freezing diplomatic relations, though he never followed this through.

After the United States, Spain is perhaps the most influential country in South America, with billions invested throughout the continent, and the strained relations were also a legitimate diplomatic embarrassment.

Spain had previously been on reasonably good relations.

Military ties

The Venezuelan leader has been making headlines since he began the European leg of his six-nation tour earlier this week.

In Moscow, he said that military cooperation with Russia was proceeding "at full speed".

News reports had also suggested Russia might open a military base in his country, but the Venezuelan government said in a statement on Wednesday that no such offer was made.

In Belarus, he praised Alexander Lukashenko, the country's president, saying their two nations shared a common resistance to "US imperialism".

Washington has called Lukashenko Europe's last dictator.

Chavez also visited Portugal. He is returning to Caracas late on Friday.