The 51-year-old takes over from Ellen Johnson Sirleaf, who became Africa's first female head of state when she defeated Weah 12 years ago, and steps down after two terms of six years each. It is the first time since 1944 that Liberia has witnessed a democratic transfer of power.

Weah saw off the challenge of Joseph Boakai - who beat him to the vice-presidency in 2011 - in a run-off election which was delayed after Boakai challenged the early election results in court.

Weah eventually won with 61.5 percent of the votes in the run-off elections held a day after Christmas last year.

In his first speech after his election, Weah - whose policy thrust has been something of a mystery - promised to promote national unity, encourage foreign direct investment, and tackle corruption, a challenge that his predecessor admitted she had underestimated.

"The mandate that I have received is a mandate to end corruption. It is time to put the interests of our people above our own interests and ensure that our country's resources do not end up in private pockets.

"We must pay civil servants a living wage so that corruption is not an excuse because you will be prosecuted to the full extent of the law.

"I promise to do everything in my power to be the agent of positive change. But I cannot do it alone. I call on the legislature to work with me to pass laws that will complete the foundation of our nation."

Jewel Taylor, the ex-wife of former Liberia president Charles Taylor - who is in a UK prison for war crimes - will be Weah's vice-president.

Weah during his heyday at PSG 

Named by FIFA as Africa's Player of the Century, Weah is one of the most decorated stars of world football, becoming the first and only player to win the African Player of the Year, European Player of the Year and World Player of the Year awards at the same time.

For a man whose life is steeped in football, it was no surprise that Weah opened his speech with football symbolism.

"I have spent many years of my life in stadiums, but today is a feeling like no other. I guarantee you that when we finish, there will not be a winner or a loser. Today we all wear the jersey of Liberia. And the victory belongs to the people."