The 56-year-old South African today became the sixth ICC chief, following in the footsteps of Lord (Colin) Cowdrey (1989-93), Sir Clyde Walcott (1993-97), Jagmohan Dalmiya (1997-2000), Malcolm Gray (2000-3) and Ehsan Mani (2003-6).
Addressing the ICC Business Forum at it's spiritual home Lord's, Mr Sonn also revealed that he was planning an early Zimbabwe visit to assess the situation there.
''Cricket is stronger than it has ever been. But at the same time it is not without its issues. Zimbabwe has seen many of its players walk away from the national side and Zimbabwe cricket is weaker,'' he said, referring to the plight of the game in the country which saw former skippers Heath Streak and Tatenda Taibu quitting the national team. Besides, allegations of financial bungling against top administrators have dealt a severe blow to the game in Zimbabwe.
Mr Sonn said he wanted to have a first hand knowledge of the situation.
''I will then report back to the ICC's executive board so we are in a better position to support Zimbabwe cricket at a time when support is clearly needed,'' he explained.
On his appointment, he said, ''Standing here as the first South African president of the ICC is a very humbling experience, especially as it is not something that could have happened a generation ago.'' Meanwhile, congratulatory messages flowed from all quarters after his appointment with South Africa President Thabo Mbeki leading the tribute.
''The ICC was the first international sports body to recognise a democratic South Africa through the membership of the United Cricket Board of South Africa in 1991,'' said Mr Mbeki.
''Mr Sonn played a major role in the unification of South African cricket that led to this membership and his leadership of the ICC will be another important step in his administrative career. The President, Government and the people of South Africa congratulate Advocate Percy Sonn on his appointment as President of the ICC, the first South African to hold this post,'' added the President.
Ehsan Mani, whose three-year reign as President ended today at the ICC's annual conference at Lord's, was equally full of good wishes and praise for his successor.
''Percy has served as ICC Vice President for the past two years and is a former President of the United Cricket Board of South Africa. He brings a wealth of experience and a deep understanding of the issues in the game (to the role of ICC President).
''He will have the support of a well-structured and properly resourced organisation complemented by an excellent management team.
I extend my best wishes to Percy during his term as ICC President,'' he said.
Congratulations also came from the Chief Executive of the United Cricket Board of South Africa, Mr Gerald Majola, and South Africa's captain, Graeme Smith.
''The South African nation and the cricket community in particular, acknowledge with much pride the inauguration of Advocate Percy Sonn, S.C. as President of the ICC," said Mr Majola.
''It says much for the South African and international cricketing fraternity that the young boy who learnt his cricket in dusty townships during the apartheid era has now risen to head the family of world cricket.
''Advocate Sonn was a pioneer of the struggle against apartheid, as well as a pioneer of the unification of South African cricket that led to the membership of the ICC by the United Cricket Board of South Africa,'' he said.
Graeme Smith said, ''It is a wonderful feather in South African cricket's cap to have Advocate Percy Sonn as President of the ICC.
We in cricket are always striving to get to the top, and it is great to see an able and committed administrator such as Advocate Sonn reaching the highest office.
''We are confident that his leadership will do much towards world cricket meeting the challenges that face all of us because of his in-depth knowledge of the needs of the game at all levels,'' added the Proteas captain.
Mr Sonn's appointment as ICC President follows two years as the organisation's Vice-President, a post to which he was appointed on 1 July 2004. He will serve as ICC President for a minimum of two years and a maximum of three years.