Pakatan Harapan has threatened to lead the rakyat in a "political action" on July 30, if its three demands, including its call for Prime Minister Najib Abdul Razak go on leave, are not met by Friday next week.

In a joint statement by the pact's presidential council today, they also want the cabinet to call for a Royal Commission of Inquiry (RCI) and an emergency Parliament session, failing which they will resort to the "political action".

However, it is uncertain what form of political action it would take as they did not give any details.

The statement was jointly signed by PKR president Dr Wan Azizah Wan Ismail, Parti Amanah Negara president Mohamad Sabu and DAP acting national chairperson Tan Kok Wai.

They said that Malaysians and the whole world were shocked following the press conference held by the United States Department of Justice last night announcing that it is seeking to seize assets worth in excess of US1 billion (RM4 billion) that were allegedly acquired using funds misappropriated from 1MDB.

"This is the largest seizure of illegal assets in American history where between 2009 and 2015, close to US3.5 billion or RM14 billion was illegally taken out from 1MDB by several individuals including by Riza Aziz, who is Najib's stepson and his associate, financier Jho Low, all with the knowledge and approval given by an individual only referred to as 'Malaysian Official 1," read the statement.

Following the serious allegations and its implications, Harapan urged Najib to take leave from his office immediately.

The opposition pact said that if Najib stays, he would be perceived to have power and influence over several agencies investigating the case, namely the federal government, the Attorney-General's office, the police and the Malaysian Anti- Corruption Commission.

They also urged the cabinet to advise the Yang di-Pertuan Agong to declare the formation of an RCI to investigate the serious allegations and call for an emergency parliamentary session where Najib can explain the matter to lawmakers.

The presidential council gave an ultimatum to Najib: if he or the cabinet does not implement any of the three demands by July 29, Pakaran Harapan would mobilise the people in a "political action" on July 30 to register their protest against Najib.