Silvio Berlusconi leaves Angela Merkel waiting while he takes a phone call
First he complimented Barack Obama's "tan", then he played hide and seek with the German leader. He has even annoyed the Queen by being too loud.
Now Italian Prime Minister Silvio Berlusconi has held up the start of a key Nato summit - by talking for too long on his mobile phone.
In his defence, Mr Berlusconi was talking to Turkey's prime minister in a bid to resolve a row at the summit.
But Germany's leader was kept waiting on the red carpet for several minutes.
Angela Merkel had just led Nato leaders from Germany across a bridge straddling the River Rhine to meet President Nicolas Sarkozy coming from Strasbourg on the French side.
Mr Berlusconi joined the group shortly afterwards.
Mrs Merkel looked bemused as the Italian's call dragged on and finally opted to start the event's opening ceremony without the Italian.
It emerged later that Mr Berlusconi had been speaking to his Turkish counterpart in Istanbul, Recep Tayyip Erdogan, in an attempt to persuade Turkey to drop its opposition to Danish Prime Minister Anders Fogh Rasmussen as Nato's new chief.
In the event, Turkey did concede, with Mr Erdogan saying it had been swayed by US President Barack Obama's assurances.
The Italian leader has developed a reputation for gaffes, outspoken comments and playful behaviour, even on the world stage.
The latest incident comes just days after the Queen appeared to express mild irritation when Mr Berlusconi noisily greeted US President Barack Obama at a photo-call in London.
Last year he was filmed apparently playing "hide and seek" with Mrs Merkel in Trieste, hiding behind a large column as she walked past.
Earlier, he came under fire for describing Barack Obama as "young, handsome and tanned". Mr Berlusconi has palmed off the criticism those comments prompted, saying it emanated from humourless "imbeciles".
Mr Berlusconi's previous practical jokes at formal gatherings include making the Italian horned cuckold gesture behind a Spanish minister during a group photo of EU leaders in 2002.
The billionaire media mogul then sparked a minor diplomatic incident in 2005 by suggesting he had used "playboy tactics" to woo Finnish President Tarja Halonen in order to ensure her backing for Italy to host the European Food Safety Authority.
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