The mainland official in charge of pre-handover land grants yesterday rejected suggestions rocketing property prices were a result of China's alleged tight grip on land supply in recent years. Chen Rongchun, Chinese leader of the Sino-British Land Commission, said the amount of residential land made available in each of the past three years was twice the area granted previously. During the commission's 12 years, 620 hectares of residential land were put up for development. Despite the increase, prices of small and medium-sized flats have risen 30 per cent since May last year. Speaking after the final meeting of the commission, Mr Chen said: 'Property prices in Hong Kong rise and fall. This is absolutely normal . . . it should not be viewed as the result of land supply alone.' Mr Chen said the Land Commission was not the only source of land. Other sources were Government change of land use, private developers and inner city redevelopment. In January, Financial Secretary Donald Tsang Yam-kuen accused Mr Chen of not being 'sympathetic' to land demand. But Mr Chen said: 'We have granted an average of 52 hectares for residential land use per year - far exceeding the Joint Declaration Annex Three requirement of a 50-hectare limit. 'This is an illustration of China's concern for the housing problems of the people of Hong Kong.' His British counterpart, Secretary for Planning, Environment and Lands Bowen Leung Po-wing, said he believed the post-handover government would note the demand and increase land supply.