The son of Palestinian president Mahmouud Abbas owns $1m worth of shares in a Palestinian investment company, the Panama Papers have revealed.

In the mega-leak of documents from Panamanian law office Mossack Fonseca, published by over 100 news organisations two weeks ago, are the files of the Arab Palestinian Investment Company (APIC), incorporated in the Virgin Islands in 1994.

According to Haaretz, the company has been involved in myriad deals to import goods into the Palestinian Authority. Although it is privately-owned, the Palestinian Investment Fund — which is controlled by the Palestinian President’s office — owns 18 per cent of APIC.

The financial adviser to Palestinian leader Yasser Arafat, Mohammed Rashid, was a director of APIC before 2004. However, after Arafat’s death, most of the directors were replaced by loyalists to Mr Abbas.

In 2011, Tareq Abbas was appointed a director in APIC. The Panama Papers reveal that he also owns, as of last September, $982,000 worth of shares in the company. Along with his brother, Yasser, the sons of President Abbas are invested in a number of trading companies active within the Palestinian Authority which have successfully bid for contracts from international aid organisations working in the PA.

Other revelations from the Panama Papers have failed to cause much of a stir in Israel. Prominent names published in relation to the offshore accounts and shell companies include those of lawyers Yaakov Weinroth, who was Prime Minister Benjamin Netanyahu’s private attorney; Dov Weinglass, who served as the late prime minister Ariel Sharon’s chief of staff; and billionaire jewel magnate Dan Gertler.

Senior officials in Israel’s tax authority said that they were investigating certain names among at least 850 Israelis mentioned in the Mossack Fonseca documents. It added, however, that many had declared their holdings and it was unclear at this stage if any had engaged in illegal tax avoidance or money laundering.