evidence: Both sides invoked sovereignty to defend their claims. Singapore’s government described Malaysia’s move as encroaching "Singapore’s territorial waters off Tuas". Finance Minister Heng Swee Keat claimed Malaysia’s move was a violation of international law. Other Singaporean ministers accused Malaysian government vessels of intruding its territorial waters. [...] The dispute should be understood in its broader historical context. In 1979, Malaysia mapped its sea territory, provoking protests from Singapore. In 1995, Malaysia and Singapore agreed upon (most of) a maritime boundary in the Johor Strait. In 1999, Malaysia published its amended Johor Bahru port limits, which corresponded to the territorial sea limits claimed in its 1979 map. The new moves extend the port limits beyond Malaysia’s 1979 territorial claim. [...] Another key maritime and territorial issue has been the ownership of Pedra Branca – a small island located at the eastern entrance of the Straits of Singapore – as well as two maritime features, Middle Rocks and South Ledge, a low-tide elevation. In 2008, the International Court of Justice awarded Singapore sovereignty of Pedra Branca. Malaysia filed an application to have the case reopened on the basis of new historical records, however, this last-ditch effort was abandoned in 2018.