Marco Benatti's personal assistant told a court today it would "not be his style" to write a libellous blog about Sir Martin Sorrell.

WPP boss Sir Martin has accused Mr Benatti, who was WPP's "country manager" in Italy until his dismissal in January 2006, of masterminding a series of blogs that likened him to a mafia don.

He is suing Mr Benatti and his lieutenant Marco Tinelli for libel and also for invasion of privacy over a "grossly offensive" image of Sir Martin and female executive Daniela Weber. Both men deny any responsibility for the blogs or the image.

"I know Marco Benatti very well indeed. I would be very surprised if he was responsible for the blog," Mr Benatti's PA, Silvia Arbasino, told the high court in London in her witness statement. "It is simply not his style."

She was "amazed" when she heard Sir Martin was taking legal action alleging that Mr Benatti and Mr Tinelli were responsible for the blog.

Ms Arbasino said she had felt embarrassed for Mr Benatti when she read the blog, which first appeared in March last year, because it alleged that he had had a relationship with Ms Weber.

She said this claim - which has always been denied by both Mr Benatti and Ms Weber - "deeply hurt" him.

"Given his close brotherly relationship with Daniela over the years, it was not nice for him or Daniela to be linked in this way."

"The allegations made in the blog about Daniela Weber cheating on 'Don Martino' with 'the Italian partner' were absolutely false," she added. "I can categorically say that to the very best of my knowledge they never had any sort of sexual relationship."

She said her own reaction on reading the blog had included "some amusement".

"It must be remembered that this blog appeared at a time when [Mr Benatti's ad group] FullSix and Marco Benatti had been facing a very difficult time, largely due to WPP and Sir Martin Sorrell.

"It would be unrealistic to say that there was not an element of amusement in reading these things about Sir Martin Sorrell, given the situation we were in at the time.

"I remember clicking on the link entitled 'Poisoned Dwarf' which led me to another website criticising Martin. It struck me that he had many enemies and critics."

The case has adjourned for the week and will continue on Monday.

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