Israel's decision not to sell an advanced airborne radar system worth US$250 million (HK$1.94 billion) to the mainland drives a wedge into one of Beijing's most complex and intriguing military relationships. Forged long before the two nations even formally recognised each other eight years ago, the relationship until yesterday had proven mutually beneficial - providing the mainland with a new avenue of cutting-edge technology while giving Israel another commercial outlet for its vast military-industrial machine. The importance of the link - in the face of increasing public and private pressure from Washington - was underscored by both President Jiang Zemin and his Israeli counterpart Ehud Barak earlier this year. Mr Jiang made Israel the focus of his visit to the Middle East in April, while Mr Barak happily vowed the sale would go ahead on his own visit to Washington a week later. Israel's aid-dependent link to the United States - its closest ally - has in the end proved stronger. The decision pleases both the White House and the US Congress. 'Israel will not do anything to harm the United States,' a spokesman for Mr Barak said yesterday. Now all eyes in Washington are on how the relationship develops from here. 'The deal is off but we expect the relationship to continue further down the track,' one Clinton administration official said. 'Both sides may have learned some hard lessons though . . . we may not see another big-ticket like this one for a while.' The order involved three Phalcon radar systems and would have proved the most expensive purchase in an order book that some estimates suggest have been worth as much as US$1.5 billion over the past five years. Fitted into giant Russian-built Il-76 transport planes - purchased from Moscow with Israeli assistance once again - the Phalcons would have allowed airborne command and control systems for extensive deployment of aircraft. The Phalcon sale was being planned despite earlier hiccups in the relationship - one eyed nervously by the Pentagon ever since intelligence officials noticed unmarked Israeli gun turrets on Chinese tanks in 1989. Israel has recently been helping the mainland in its long-term plans to build its own jet fighter, the so-called F-10, and is suspected of having passed on US technology as part of the drive. It has also reportedly sold Patriot surface-to-air missiles and other leading projectiles to China.