Srivijaya's main foreign interest was nurturing lucrative trade agreements with China which continued from the Tang Dynasty to the Song era. Srivijaya had religious, cultural and trade links with the Buddhist Pala Empire of Bengal, as well as with the Islamic Caliphate in the Middle East. The kingdom ceased to exist in the 13th century due to various factors, including the expansion of the Javanese, Singhasari, and Majapahit empires