SINGAPORE - Singapore on Wednesday (May 24) filed its rebuttal to Malaysia's application to revise a 2008 judgment that awarded sovereignty of Pedra Branca to the Republic.

In a statement on Thursday, Singapore's Ministry of Foreign Affairs said the written observations filed with the International Court of Justice (ICJ) are a "comprehensive rebuttal" to the application Malaysia submitted in February.

Both parties will present their oral arguments next, after the ICJ fixes the schedule for oral proceedings.

"Singapore is confident of our case and our legal team," the ministry said.

The Republic's legal team is helmed by former Deputy Prime Minister and Law Minister S. Jayakumar, Ambassador-at-Large Tommy Koh and former chief justice Chan Sek Keong - the leading figures in the original team on the Pedra Branca case - as well as Attorney-General Lucien Wong.

In a Facebook post, Foreign Affairs Minister Vivian Balakrishnan said: " Their wisdom, experience, and guidance has been invaluable to the younger lawyers on the team."

It took a "whole-of government effort" to produce the written observations, he added.

The work involved the Attorney-General's Chambers, National Archives, Maritime and Port Authority of Singapore, the Ministry of Defence, the Ministry of Law, and the Ministry of Foreign Affairs.

Said Dr Balakrishnan: "Their collective effort has been tremendous, and there is a strong sense of unity and purpose as we prepare for the oral arguments at the ICJ."

Malaysia had cited three "new facts" in its 42-page application to argue that "Singapore's officials at the highest levels did not consider that Singapore had acquired sovereignty over Pedra Branca from Johor" in the years following 1953.

It pointed to three documents - the first is a confidential telegram from Singapore's top colonial official to the British Secretary of State for the Colonies in 1958, which Malaysia says shows that he "did not consider the island of Pedra Branca to be part of Singaporean territory".

The second is a report about a naval incident near Pedra Branca.

The third document is a map of naval operations in the Malacca and Singapore straits from 1962.

Malaysia said two of the documents, from the United Kingdom National Archives, were declassified after the 2008 judgment. The third document's release date is unknown.

It based its application on Article 61 of the ICJ's Statute, which provides that an application to revise a judgment may be made when there is discovery of a fact that would be a "decisive factor" and was not known at the time of judgment.

The request for revision must be filed within six months of the new fact being found - in this case, Aug 4, 2016 - and 10 years of the judgment, which means the window for filing it closes next year.

The ICJ had considered correspondence from 1953 between Singapore's colonial officials and Johor as being of central importance in determining the sovereignty of Pedra Branca.

Johor's top official had written in a 1953 letter that "the Johor government does not claim ownership of Pedra Branca". The court found this showed that while Johor had the original title, "as of 1953, Johor understood that it did not have sovereignty over Pedra Branca".

The territorial dispute between Singapore and Malaysia had also involved two smaller maritime features, Middle Rocks and South Ledge, near Pedra Branca.

The ICJ, in its 2008 judgment, found that sovereignty over Middle Rocks belongs to Malaysia.

It did not make a definitive ruling on the third rock of contention, South Ledge, which is visible only at low tide. South Ledge belongs to whoever owns the territorial waters it sits in, said the court.

The three features in the Singapore Strait are located about 40km east of the Republic's main island.