Middle East and North African leaders and their families have used secret offshore accounts to stash billions of dollars of cash and manage investments and assets, according to information from the so-called "Panama Papers" leak.

The details of the financial lives of many leaders were contained in the leak of 11.5 million tax documents from the Panamanian offshore law firm Mossack Fonseca.

The documents, which have been seen by more than 100 media groups, were reported on Sunday and have been described as the biggest data leak in history. It reveals the hidden offshore dealings of 140 political figures, including 12 current or former heads of state.

Among them are leaders or close associates and family members from the Arab world, including Qatar, the UAE, Saudi Arabia, Iraq, Jordan, Syria, Egypt and Morocco.

The vast stash of records for the first time details some of the financial dealings carried out by the wealthy leaders and their relatives, revealing how vast property portfolios and bank accounts are managed through a network of companies mostly registered in the tax haven of the British Virgin Islands.

The Mossack Fonseca documents detail more than 40 years of their work for clients that include at least 33 people and companies blacklisted by the US for wrongdoing, such as some Iranian interests and those of Lebanon’s Hezbollah.

The documents were provided by an anonymous source to German newspaper Sueddeutsche Zeitung, who shared them with media worldwide through the International Consortium of Investigative Journalists (ICIJ).

The BBC cited Mossack Fonseca as saying it had operated "beyond reproach" for 40 years and had never been charged with criminal wrongdoing.

Panama's government vowed on Sunday to "vigorously cooperate" with any legal probe that might follow in the wake of the data leak.

Here is a breakdown from the ICIJ of the documents that relate to leaders and their relatives from the Middle East and North Africa.

The leaders

Qatar

Emir of Qatar Sheikh Hamad bin Khalifa al-Thani (L) and Qatari Prime Minister and Foreign Minister Sheik Hamad bin Jassim al-Thani (R) attend the opening of the Doha Forum (AFP)

Former prime minister Sheikh Hamad bin Jassim bin Jaber al-Thani bought a company in 2002 that was registered in the British Virgin Islands and three others in the Bahamas.

Through these companies Thani, who is popularly known as HBJ and is worth an estimated $7bn, managed his $300mn super-yacht al-Mirqab.

In 2011, HBJ bought four companies in Panama who held bank accounts in Luxembourg, where Qatar had recently started investing due to its low taxation, according to documents dated July 2013.

The ICIJ did not reveal how much money was held in these accounts but they did reveal that two of his accounts were co-owned with the then Emir of Qatar Sheikh Hamad bin Khalifa al-Thani, who also features in the Mossack Fonseca leak through the ownership of a company in the British Virgin Islands.

The ICIJ published a copy of HBJ’s passport which was included in the leak, which showed his diplomatic status, something which the former prime minister has used recently to avoid prosecution in Britain over allegations he had a British citizen falsely imprisoned and tortured.

A spokesperson for HBJ told the ICIJ that they didn’t “have the right” to answer any questions about the leaked documents because he is “bound by professional secrecy”.

United Arab Emirates

Emirati President Sheikh Khalifa bin Zayed al-Nahayan (L) looks at a photo exhibition including an image of himself with Britain's Queen Elizabeth II (AFP)

President Khalifa bin Zayed bin Sultan al-Nahyan was the owner of at least 30 companies established in the British Virgin Islands by Mossack Fonseca.

Through these companies the Emirati leader controlled a vast portfolio of luxury properties worth at least $1.7bn that he owns in the upmarket London districts of Kensington and Mayfair.

The purchase of the properties, according to the documents, was financed by loans from the London branch of the National Bank of Abu Dhabi and the Royal Bank of Scotland.

Mossack Fonseca handled the president’s dealings sensitively, and in 2011 the law firm wrote in one leaked document that he was "usually hesitant" about providing information about his identity.

A British law firm that represents Nahyan told the ICIJ that it was "unable to help" with comments on the leak.

Saudi Arabia

Saudi King Salman bin Abdulaziz arrives to attend the inauguration ceremony of the Yanbu Aramco Sinopec Refining Company (YASREF) project (AFP)

King Salman took out loans in 2009 of $34mn for mortgages on his luxury central London homes.

The king’s role is not specified in the documents, according to the ICIJ, but the mortgages are said to be "in relation to" him and his assets.

The documents also name the king as the principal user of a motor yacht called Erga, after his palace in Riyadh.

The Saudi embassy in the US did not respond to the ICIJ when asked to comment on the leak.

Saudi Arabia is currently struggling with a huge budget emergency, which has forced it to consider selling stakes in its oil business to create a $2 trillion wealth fund.

Mohammed bin Salman, the deputy crown prince, on Sunday told Bloomberg that the Saudi government was to introduce a sales tax within four years to raise $10bn a year, "restructure" subsidies to generate $30bn a year, and drum up $10bn a year by charging companies who recruit more foreign workers than their official quotas.

Iraq

Iraqi interim Prime Minister Iyad Allawi meets with local politicians and tribal leaders at ousted leader Saddam Hussein's hometown of Tikrit (AFP) The former prime minister, Ayad Allawi, used a company registered in Panama at least in part to manage valuable property he owns in London.

Allawi, who opposed the late former leader Saddam Hussein in exile before becoming prime minister in 2004 following the US-led invasion, was the sole shareholder of IMF Holdings, according to the leaked Mossack Fonseca documents.

As of April 2013, the documents showed that the company was registered through the company with an estimated value of $1.5mn.

Allawi had another company registered in Panama, Moonlight Estates Limited, and this also had London property registered under its ownership, however; the ICIJ did not report its value or status.

A media office representing Allawi told the ICIJ that the IMF company was established to own residential property owned by the former prime minister of Iraq.

They said that "any income generated in the United Kingdom from the properties owned by the companies has been properly accounted for" and "taxes have been paid promptly and on time".

Jordan

Ali Abu Ragheb attends a parliament meeting in Amman 14 August 2003 (AFP)

Former prime minister Ali Abu al-Ragheb owned several companies registered in the British Virgin Islands and Seychelles, which he co-directed with his wife Yusra.

The British Virgin Islands company was named by the ICIJ as Jaar Investment Ltd, which held a bank account for Ragheb and his wife in Switzerland’s Geneva.

This company was inactivated in August 2008.

Ragheb served as Jordan’s prime minister from 2000 until 2003, when he resigned and joined the boards of leading Jordanian finance and insurance companies.

The Mossack Fonseca documents also showed that until December 2014 Ragheb owned three Seychelles companies, as well as revealing that his sons were listed as directors in numerous other British Virgin Islands’ companies, including Desertstar Investment Capital Limited, which held a bank account at the Arab Bank in Geneva and was used to invest in Jordan.

The family of the leaders

Syria

Rami Makhlouf cofounded Syriatel, and subsequently took 73 percent of shares in the telecom company, most of which were registered with a British Virgin Islands company (AFP) Two cousins of Syrian President Bashar al-Assad, Rami and Hafez Makhlouf, used Mossack Fonseca to manage their vast and lucrative investments arising out of their relation to Syria’s head of state.

The ICIJ reported that in 2002 Rami Makhlouf cofounded Syriatel, a Syrian mobile telecom company, that he subsequently took 73 percent of shares, most of which was registered with a British Virgin Islands company he owned.

The documents showed the Makhlouf brothers had a slew of bank accounts in Geneva.

The documents showed that in February 2011, around the same time protests broke out against Assad, staff at Mossack Fonseca discussed via email allegations of bribery and corruption made against the Makhlouf family and sanctions imposed by the United States Treasury Department, according to the ICIJ.

In June 2011 the British Virgin Islands Financial Services Commission wrote to Mossack Fonseca regarding a money laundering investigation against the family, which prompted the law firm to subsequently cut ties with the Makhlouf family.

Neither of the two Makhlouf brothers responded to calls for comment made by the ICIJ.

Egypt

An image grab taken from Egyptian state TV shows Alaa Mubarak, son of ousted Egyptian president Hosni Mubarak, sitting behind bars (AFP)

Alaa Mubarak, the eldest son of former president Hosni Mubarak, owned the British Virgin Islands registered company Pan World Investments Inc, which was managed by Credit Suisse.

When his father was pushed out of power in 2011, Alaa was arrested by Egyptian authorities and British Virgin Islands authorities told Mossack Fonseca to freeze Pan World’s assets on the basis of European Union legislation.

The Panamanian law firm was fined $37,500 in 2013 for failing to properly carry out checks on Alaa Mubarak who was defined as a "high-risk customer".

Documents reported by the ICIJ showed that Mossack Fonseca admitted their procedures were “seriously flawed” and later investigations against Mubarak prompted staff at the law firm to admit they could be found “in further breaches”.

Mossack Fonseca staff said they had “very little control” over Mubarak’s Pan World company and in April 2015 they resigned as its agent.

Alaa Mubarak did not respond to the ICIJ when asked to comment on the leak.

Morocco

Private Secretary to Morocco's king Mounir Majidi (AFP)

Mounir Majidi, the private secretary of Morocco’s King Mohammed VI, oversaw the multi-million dollar transactions of a company registered in the British Virgin Islands that bought a luxury car used by the king and executed an expensive renovation of a Paris apartment.

Majidi, who became the king’s private secretary in 2000, was appointed the head of SIGER in 2002, which is the holding company of Morocco’s royal family that controls their interests in mining, agriculture, and telecommunications.

Majidi, with power of attorney control over the SMCD company, purchased in January 2006 a luxury 1930s yacht, the Black Douglas, which was later named El Boughaz I and is now owned and used by the king.

In 2003, a Luxembourg-registered company which Majidi administered borrowed $42mn from a Mossack Fonseca incorporated company to buy and renovate a luxury Paris apartment, according to the ICIJ.

A lawyer representing Majidi told the ICIJ that the business dealings were done “in strict accordance with laws”.