Singapore, officially the Republic of Singapore, is an island country off the southern tip of the Malay Peninsula, 137 kilometres (85 mi) north of the equator, in the Southeast Asian region of the Asian continent. It is separated from Malaysia by the Straits of Johor to its north, and from Indonesia's Riau Islands by the Singapore Strait to its south. A city-state, Singapore is the world's fourth leading financial centre and a cosmopolitan world city, playing a key role in international trade and finance.