Indonesia and Malaysia agreed on Saturday to conduct joint patrols of a disputed maritime border, an Indonesian navy commander said amid rising tensions over an oil concession in the area.

"We decided to conduct joint patrols to avoid provocative actions," Colonel Marsetyo told Elshinta radio.

The Indonesian navy had dispatched four warships to the disputed area off the coast of Sabah and Indonesia's East Kalimantan province.

Tensions had risen between the countries after Jakarta protested a move by Malaysia's state oil company Petronas to grant energy giant Shell a concession in the area on Feb 16.

Jakarta says the area is part of its territorial waters and some of the concession granted by Malaysia overlaps with one granted by the Indonesian government to Italy's ENI and the US company Unocal in the 1960s.

The Indonesian government has sent a formal protest to Malaysia over the matter.

Najib downplays border row

Malaysia's Deputy Prime Minister Najib Razak on Saturday downplayed the row, saying diplomacy rather than military strength was needed to resolve the row.

"It is not Malaysia's way to use the military to resolve a conflict, Najib, who is also defence minister, was quoted as saying by Bernama news agency in the eastern Sabah state on Borneo island.

"We don't want to blow up this matter. We leave it to the foreign ministries of both countries to handle the issue," he added.

Indonesia and Malaysia previously disputed the ownership of two small islands near the same area in the Sulawesi Sea.

But in December 2002, the International Court of Justice ruled that the islands - Ligitan and Sipadan off Borneo island - belong to Malaysia.