The claim was confirmed through its map which it published in 1979. Indonesia protested the delimitation on the map. The dispute was brought before the International Court of Justice and on 17 December 2002, decided that sovereignty of Sipadan and Ligitan belonged to Malaysia on the basis of "effectivités". It however did not decide on the question of territorial waters and maritime borders. This allowed the dispute over territorial waters and continental shelf to remain unresolved. The dispute over the Ambalat block (see below) can be seen to be part of this dispute over territorial waters and continental shelf. Ambalat is an area of the seabed or continental shelf in the Celebes Sea off the east coast of Borneo which is claimed by Indonesia and Malaysia. The seabed is believed to be rich in crude oil. Contrary to popular belief, the International Court of Justice decision over the sovereignty of Sipadan and Ligitan did not solve the dispute over Ambalat as it did not include issues concerning the demarcation of the territorial sea and continental shelf boundaries of the two countries in the area. The dispute started with Malaysia issuing a map in 1979 of its territorial sea and continental shelf which included the Ambalat block. The map drew Malaysia's maritime boundary in a southeast direction into the Celebes Sea after it leaves the eastmost point on land on Sebatik island. This would include the Ambalat block, or a large part of it, within the Malaysian continental shelf. Indonesia has, like the other neighbours of Malaysia, objected to the map. Indonesia has never officially announced the exact locations of its maritime boundaries but claimed during its arguments in the Sipadan Case that it continued in a straight line along the 4° 10' North latitude after it leaves Sebatik. Both countries have also awarded exploration contracts to oil companies for the area. Indonesia has awarded concessions to ENI of Italy for what it called the Ambalat Block in 1999 and US company Unocal for East Ambalat in 2004. Petronas, the Malaysian petroleum company, meanwhile awarded a concession over what Malaysia called Block ND 6 and ND 7 in February 2005. A large part of Ambalat overlaps with Block ND 6 while a huge portion of East Ambalat overlaps with Block ND 7. The dispute has created considerable tension between the two countries, with several facing-off incidents between the navy ships of both countries. The latest round of tension occurred at the end of May 2009 when Indonesian media reports stated that Indonesian navy ships were close to firing shots at a Malaysian navy vessel which it claimed had encroached deep into Indonesian territorial waters.