Singapore's Deputy Prime Minister S. Jayakumar will make a four-day official visit to Saudi Arabia starting Sunday, the government said in a statement. The official visit is a follow-up to Senior Minister Goh Chok Tong's trip to the kingdom in February to strengthen bilateral ties, the Associated Press quoted the statement as saying. Jayakumar will be accompanied by the junior minister of trade and industry Heng Chee How and senior representatives from the central bank, tourism board and foreign ministry. A Singapore business delegation will also be visiting.