Light's refusal caused the Sultan to strengthen Kedah's military forces and to fortify Prai, a stretch of beach opposite Penang. Recognising this threat, the British moved in and razed the fort in Prai. The British thereby forced the Sultan to sign an agreement that gave the British the right to occupy Penang; in return, the Sultan would receive an annual rent of 6,000 Spanish pesos. On 1 May 1791, the Union Flag was officially raised in Penang for the first time. In 1800, Kedah ceded Prai to the British and the Sultan received an increase of 4,000 pesos in his annual rent. Penang was later named Prince of Wales Island, while Perai was renamed Province Wellesley.