The allegation by international media the Wall Street Journal (WSJ) against prime minister Datuk Seri Najib Tun Razak is not acceptable because it is not substantiated by concrete proof and documents, said Umno Youth head Khairy Jamaluddin.

He said that the disclosure by WSJ that almost US$700 million (RM2.6 billion) was credited into Najib's personal accounts was based on the report by the portal, Sarawak Report, whose authenticity was disputed.

"Anyone can make accusations and disclosures, but if there is no concrete evidence, we cannot accept such disclosures.

"In this case (WSJ allegation), I don't see any concrete proof, they say there are documents but no documents have been submitted until now," he told reporters after attending the ceremony to hand over Ramadan contributions at the Bandar Beris Baharu Mosque, here today.

The Youth and Sports Minister said that in terms of legal principles and the court, the burden of proof on any allegation lies with the accuser and not the accused.

Asked whether the Prime Minister and 1Malaysia Development Berhad (1MDB) should take legal action against WSJ, he said it was up to the two parties concerned.