In May 2008, Al-Azhar passed a fatwa under which 20% of revenues from oil and other tapped underground natural resources must be allocated to charity. Prominent Islamic sheikh Dr. Yousef Al-Qaradhawi objected to the fatwa, and it was issued in Saudi Arabia only much later. The fatwa's release had already been delayed for seven years in Egypt, as it awaited Al-Azhar's approval.
Following are excerpts from an article discussing the fatwa, in the Egyptian weekly Roz Al-Yousef: 
The Fatwa is Based on the Koran and the Hadith
The fatwa, which stipulates that 20% of all tapped underground natural resources should be allocated to charity, was authored by "an Egyptian Islamic philosopher, Dr. Muhammad Shawqi Al-Fanjari, who had held a senior position on Egypt's State Council before emigrating to Saudi Arabia, where he lectured on the Islamic economy...
"In light of the ongoing rise in oil prices, which began with the October 1973 war... Al-Fanjari felt the need to implement the fatwa [found in the Islamic sources] regarding [the allocation to] charity of part of earth's natural resources.
"[Fanjari believes that] this fatwa is not based on ijtihad [independent intellectual judgment]; he maintains that it is laid down in the Koran and is endorsed by a reliable hadith...
"According to [Al-Fanjari's research on these sources, the fatwa states that] a fifth [of all revenues from tapped underground natural resources] be allocated for charity. According to Imam Ahmad bin Hanbal [founder of the Hanbali school of Islamic jurisprudence, which is followed in Saudi Arabia], this refers to everything beneath the ground, whether liquid or solid - [including] oil, minerals, and other underground natural resources, [and] possibly even objects unearthed by archaeological excavation...
"Al-Fanjari presented his research at the First International Conference on Islamic Economy, held in 1976 in Mecca... He contended that if oil-producing Arab countries were required to allocate 20% of all oil revenues to charity, and if these proceeds were managed by banks [specially] designated to carry out transactions with charity [funds], not a single needy individual would remain in the Islamic world. [In addition,]social justice would be achieved, and the international mission of Islam would be accomplished.
"In this way, the profit [earned by charity funds accrued from oil revenues] would be distributed among the needy and among the victims of disasters worldwide. The remaining 80% of oil revenues, Fanjari believed, would be more than enough to supply oil-producing countries with all their needs..."
"Dr. Al-Fanjari included his research... in one of his books... [He] insisted that he had not composed the fatwa but merely uncovered it, since it is explicitly and clearly spelled out in the books of Islamic law.
"Al-Fanjari refers to the Koranic verse 'O ye who believe! Give of the good things which ye have (honorably) earned, and of the fruits of the earth which We have produced for you... [Koran 2:267],' which lists the commodities wherefrom a portion must be allocated to charity.
"He also relies both on a reliable hadith under which a fifth [of all profits] from natural resources must [be apportioned] to charity, and on the interpretation [of this fatwa] by Imam Ahmad bin Hanbal, who includes under 'resources' everything underground, liquid or solid... although Ibn Hanbal lived when oil had not yet been discovered...
"On this issue of jurisprudence, Al-Fanjari did not rely exclusively on Ibn Hanbal's opinion but also on the viewpoint of other schools of jurisprudence. [Indeed,] religious scholars belonging to the Hanafi and Shaf'i schools [also] claimed that [a portion of revenues] from natural resources must be allocated to charity, albeit they ruled that funds thus obtained should be distributed in the region from which the minerals - or in this case the oil - had come.
"On the other hand, Imam Malik [founder of the Maliki school of religious jurisprudence], contended that anything derived from underground was considered the property of the state, and [that therefore] there was no obligation [to apportion part of the profits from it] to charity..."
Al-Qaradhawi: Arab Countries Should Not Be Required to Apportion Charity from Natural Resource Revenues
According to the article, Sheikh Yousef Al-Qaradhawi, director of the Muslim Religious Scholars Association who currently resides in Qatar, objected to the fatwa. The article said that Al-Qaradhawi argued that "the writings on allocating part of natural resources to charity should not be implemented, because oil is the property of the Arab states rather than the citizens, and because it is not the countries who donate to charity, but the citizens, while the state receives the charity donations from them.
"Al-Qaradhawi further stated that Islamic oil-producing countries were already contributing funds to help Muslims, and that therefore they should not be asked to also give part of the revenues from natural resources to charity.
"Al-Fanjari responded that Al-Qaradhawi's ruling would be valid only if the Islamic countries constituted a single state. However, he said, since they are separate states, oil revenue money is not distributed among all Islamic countries, but remains the property of those countries where the oil is actually found. Therefore, oil-producing [countries] should donate to charity, [and this charity] should then be distributed to countries that have no oil..."
Saudi Censor Objects To Fatwa, Saudi Senior Clerics Council Endorses It
The article also mentions another move, in Saudi Arabia, to invalidate both Al-Fanjari's research and the fatwa: "Under Saudi law, no book can be published without permission from an official censor... Al-Fanjari claims that the contents of his book angered the censor, who said that he could not authorize its publication, especially since Saudi Arabia had not been implementing the fatwa...
"[However,] the argument between the author of the book and the Saudi censor was resolved with the help of a third party - [then-]president of the Saudi Senior Clerics Council, [Grand Mufti] Sheikh 'Abd Al-'Aziz bin Baz, who called a meeting between the two sides and during it endorsed Al-Fanjari's [fatwa], saying that the Senior Clerics Council had recognized its legitimacy...
"The censor objected, protesting that he could not bring himself to allow the book to be published... It was agreed that 'Abd Al-'Aziz bin Baz would take theological and shari'ic responsibility for the book's publication. Moreover, the [then-]Saudi religious endowment minister... personally submitted the book's second edition for publication..."
Al-Azhar Held Up the Passage of the Fatwa For Seven Years
The article concluded: "The fatwa was held up in Egypt for seven years. In 1989, Dr. Al-Fanjari traveled back to Egypt, and in 1999 he was elected a member of the Academy for Islamic Research.
"In 2001, he submitted a study on the legitimacy of apportioning charity [from the revenues from tapped underground] natural resources, and asked the Academy to evaluate his conclusions. The study was passed on to an Islamic jurisprudence committee, and was buried for seven years.
"It was finally endorsed by a committee consisting of two Academy members - Dr. 'Abdallah Al-Nagar and Dr. Muhammad Rafat 'Othman... who consented to approve the fatwa only if the author rephrased it in terms of [donating a portion of] revenues from tapped underground natural resources to charity, or, more generally, a portion [of revenues] from anything derived from underneath the surface of the earth - instead of referring specifically to oil..."
 Roz Al-Yousef (Egypt), June 14, 2008.