Mr Nicolaides was arrested at Bangkok's airport almost five months ago

Thailand's royal secretariat is considering a pardon for Australian man Harry Nicolaides, who was found guilty of insulting the monarchy earlier this week. 

The 41-year-old Melbourne man wrote a book in 2005 which briefly referred to the private life of Thailand's Crown Prince.

Lawyers for Mr Nicolaides began the pardon process after he pleaded guilty to the charge of lese-majesty on Monday.

The pardon request will need to be processed by the corrections department before being presented to Thailand's beloved King Bhumipol.

Mr Nicolaides was arrested at Bangkok's airport almost five months ago because insulting the monarchy is a serious offence in Thailand, although foreigners are rarely prosecuted.

But in 2007 a Swiss man was sentenced to 10 years in jail for defacing posters of the King. He was later pardoned and deported.

There are 17 other cases currently before the Thai courts.

Australian Foreign Minister Stephen Smith has written a letter to his Thai counterpart this week outlining the Government's support for the pardon plea.

If he is granted a pardon, Mr Nicolaides is expected to be deported.