goods to be purchased by the Royal Warehouse. Foreigners could not directly and privately trade important profitable government-restricted goods with the native Siamese. In 1821, the Governor-General of British India, in the mission to establish trade contacts with Siam, sent John Crawfurd to Bangkok. Crawfurd arrived in Bangkok in 1822, delivering the British concern for Kedah sultan and demands for trade concessions, which turned negotiation soured. Siam sent troops to aid the British in Tenasserim in the First Anglo-Burmese War. However, a dispute prompted King Rama III to withdraw the Siamese armies from Burma. In 1825, the British sent another mission led by Henry Burney to Bangkok. The Anglo-Siamese Burney Treaty was signed in 1826, in which centuries-old royal Siamese monopoly over Western trades was ended with the British granted to trade freely in Siam. The treaty also recognized Siamese claims over Kedah. However, some trade restrictions including the Phasi Pak Ruea () or measurement duties were still intact. Siam also concluded the similar "Roberts Treaty" with the United States in 1833. Tunku Kudin, a nephew of the former Kedah sultan, reclaimed Kedah by force in 1831 and rose up against Siam. Pattani, Kelantan and Terengganu joined on Kedahan side against Siam. King Rama III sent forces under Nakhon Noi and a navy fleet under Chaophraya Phrakhlang to put down Malay insurgency. The Raja of Ligor recaptured Kedah in 1832. In 1838, Tunku Muhammad Sa'ad, another nephew of the Kedah sultan, in concert with Wan Muhammad Ali (called Wan Mali in Thai sources) the Andaman Sea adventurer, again retook Alor Setar from the Siamese. Kedahan forces invaded Southern Siam, attacking Trang, Pattani and Songkhla. King Rama III sent fleet, led by Phraya Siphiphat (younger brother of Phrakhlang), to quell the rebellion. Siamese forces recaptured Alor Setar in 1839. Chaophraya Nakhon Noi the Raja of Ligor died in 1838, leaving Malay affairs to Phraya Siphiphat. Siphiphat divided Kedah into four states: Setul, Kubang Pasu, Perlis and Kedah proper. The former Kedah sultan reconciled and he was finally restored as Sultan of Kedah in 1842. Journey of Phraya Siphiphat to the south in 1839 coincided with the Kelantanese Civil War. Sultan Muhammad II of Kelantan had conflicts with his rival contender Tuan Besar and requested for military aid from Phraya Siphiphat. Siphiphat, however, posted himself as the negotiator and forced peace agreement upon warring Kelantan factions. Tuan Besar arose again in 1840.