Sao Tome and Principle - two tiny islands off the coast of West Africa populated by 160,000 people - could be sitting on up to four billion barrels of crude oil.
Sao Tome residents hope oil will change their lives
President Fradique de Menezes - who appears to have been deposed while in Nigeria - met George W Bush last year to advertise his country's potentially rich reserves.
Sao Tome was an important "alternative source of oil outside the politically volatile Middle East," he told Mr Bush, reminding him that his country "is strategically situated on the most important petroleum area in the world today."
A Texas company Environmental Remediation Holding Corp has had rights to two offshore fields in the country's territorial waters since 1997.
Other licences to develop the offshore oil fields are due to be auctioned next year.
There is excitement about the creation by Sao Tome and Nigeria of a Joint Development Zone (JDZ) - covering an area slightly smaller than Belgium - which officials say could produce 250,000 barrels of oil a day within five years.
Last month, the islands' government took a road show to the US and the UK to start the bidding for oil licenses.
The US was reported to be interested in building a military base on the island to oversee its oil interests elsewhere in the Gulf of Guinea.
Army officers who have toppled the government and seized among others, Prime Minister Maria das Neves, Defence Minister Fernando Daqua and Natural Resources Minister Rafael Branco, may be interested in oil.
On election to office in 2001, cocoa trader President de Menezes cancelled existing oil agreements.
However, he has made enemies for other reasons, according to observers.
"He was thought to have benefited from the re-negotiations of oil contracts," Manuel Paulo from the Royal Institute of International Affairs told BBC News Online.
"He had also distanced himself from the family of his predecessor who was key in his succession."
President de Menezes came to power in an election controlled by Sao Tome's former leader Miguel Trovoada.
Despite its huge resources, the country is one of the continent's most impoverished and obscure nations.
Heavily indebted, the former Portuguese colony has relied on handouts from China, North Korea and Cuba in the past.
Today, the nation survives from ever-dwindling cocoa exports and offering shipping companies a convenient stop-over.
It also raises money by renting its telephone lines to porn operators to route telephone-sex calls - a common practice in the developing world - and by issuing commemorative stamps of Marilyn Monroe.
Oil could be flowing in five years
Taiwan reportedly provides more than $10m in aid a year in return for Sao Tome granting diplomatic recognition to the republic and severing relations with China.
But if oil starts flowing the country's fortunes could vastly improve; each citizen could be worth $1m, according to one estimate.