KUALA LUMPUR (Reuters) - Malaysia's opposition said on Thursday it will mobilize the public for a "political action" if Prime Minister Najib Razak does not immediately go on leave of absence.

Pakatan Harapan, the opposition coalition, also asked Najib to convene an emergency parliamentary sitting to provide a full explanation, following Wednesday's revelations by U.S. prosecutors that more than $3.5 billion was diverted from state-fund 1Malaysia Development Berhad.

The U.S. civil lawsuits are seeking to seize $1 billion in assets they said were tied to money stolen from the fund, which was founded by Najib.

(Reporting by Joseph Sipalan; Editing by Robert Birsel)