About 200 flats at the Royal Green development in Sheung Shui were snapped up by homebuyers during an internal sale over the weekend, as recent interest-rate increases failed to dampen sentiment in the primary market. The joint development by Henderson Land Development and SEA Holdings was the first residential project launched since leading banks last week raised their prime lending rates by 50 basis points. About 180 flats were sold on Saturday but sales slowed to about 20 yesterday, developers said. Including the 240 units pre-sold through bulk purchases, accumulated sales of the project are about 420 units so far, Henderson Land said. Prices ranged from $3,128 to about $4,000 per square foot, it said. Estate agents said the warm response to Royal Green's pre-sales showed the latest 50 basis point interest rate increase had been discounted by the market. But they also noted that many potential homebuyers remained cautious. Henderson Land general manager Tony Tse Wai-chuen was upbeat, saying the widely anticipated interest rate rise would have a short-term impact. 'We are happy with the internal sale performance. The recent interest rate increase just didn't have a negative impact on our sales,' Mr Tse said, adding developers had raised their prices 3 per cent to 5 per cent during the internal sale. Midland Realty director Lawrence Wong Wai-wing attributed the positive response to Royal Green to the developers' special mortgage offer of a fixed 0.5 per cent mortgage rate in the first year. Interest rates in Hong Kong have risen one percentage point since March, and the market expects rates to climb another 50 to 100 basis points by the end of the year. Economists estimate that a further one percentage point rise in rates this year will increase flat owners' mortgage payments by 11 per cent. The prime lending rate in Hong Kong now stands at 5.75 per cent to 6 per cent. Centaline Property Agency said the number of viewing appointments at the 10 most active housing estates fell 3.1 per cent to 885 at the weekend. Even so, the Royal Green sales office in Fanling was swamped by about 7,000 visitors to the show flats, Mr Tse said. The project, comprising three blocks of 922 still unfinished units ranging from 501 square foot to 1,319 sq ft, was also the first development launched after recent public calls to tighten internal sales due to poor transparency. The developers said they had followed the guidelines issued earlier by the Real Estate Developers' Association and carried out the internal sale in an orderly manner.