DiCaprio's charity is also an environmental organization.
Earlier this year, U.S. prosecutors tried seizing more than $1 billion in assets they said were tied to money stolen from the Malaysian state fund, overseen by the prime minister, and used to finance "The Wolf of Wall Street" film and to buy property and works of art.
During a press conference held in London today, civil society activists from Malaysia, the United Kingdom and Switzerland called on Leonardo DiCaprio to publicly disown Najib Razak's stepson, Riza Aziz, and his associate Low Taek Jho (Jho Low) who had been instrumental in funding the production of the film The Wolf of Wall Street.
At the press conference, dubbed "Recovery of Stolen Malaysian Assets", a direct link was made between the 1MDB corruption scandal and major environmental issues in Malaysia, such as deforestation, a Key concern of the Leonardo DiCaprio Foundation.
The production company, Red Granite Pictures, has said that to its knowledge none of the money it received was illegitimate and that it had done nothing wrong.
According to The Hollywood Reporter, rainforest charity Bruno Manser Funds has asked Leonardo DiCaprio to step down from his role as the UN Messenger of Peace with a special focus on climate change.
An eco-warrior against climate change and a producer of the upcoming documentary "Before the Flood" -released via National Geographic later this month- DiCaprio has aggressively advocated against global warming.
Straumann and Michel were both in London to hold a press conference along with other civil society activists from Malaysia on the 1MDB corruption scandal.
The 1MDB scandal is an ongoing probe into the alleged misappropriation of billions of dollars through a fund called 1Malaysia Development Berhad.
They also urged the actor to publicly disown Riza Aziz and his associate Low Taek Jho, two individuals instrumental in the production of "The Wolf of Wall Street".
"He needs to become part of the solution, but today he is part of the problem", he added.
"We can't save the environment if we fail to stop corruption", said Straumann, who called DiCaprio's criticism of deforestation in Borneo areas under Indonesian control, "cynical hypocrisy".
A spokesperson for the actor said in a statement that DiCaprio initiated contact with the Department of Justice back in July after learning through media reports about legal action being taken against some of the people involved in the making of his 2013 film, "The Wolf of Wall Street".