A proposed law that stands to dramatically expand United States arms sales to Taiwan, and rile Beijing, was set to take a step closer to reality in the US Congress today. The International Relations Committee of the House of Representatives was expected to override the deep concerns of the Clinton administration and back the Taiwan Security Enhancement Act. The proposal demands the US provide ballistic missile defence for Taiwan as well as advanced air-to-air missiles, planes and diesel submarines. It also formally upgrades military ties between Taiwan and the US, a relationship that is currently unofficial. Once passed in the committee, the bill is expected to move to the floor of the House for a full vote by the end of next week. When that is complete, the process will be repeated in the Senate. One senior committee aide said: 'It is hard to say if there is enough time for it to move ahead this year. But make no mistake about it, many Republican congressmen are still very keen on this bill.' The State Department, Pentagon and White House have been shrill in their opposition. A fierce lobbying effort is under way as fears mount that the bill has a good chance of passing the House, a move which would be certain to inflame Beijing. The bill may face more opposition once it gets to the Senate. The administration, backed by a string of senior academics and retired diplomats, fears the bill will effectively re-write the long-standing Taiwan Relations Act. They are worried it will shatter the aura of 'strategic ambiguity' in the act that allows the US to pledge to defend the island without formal diplomatic recognition and is a key plank in Sino-US relations. 'We have made exceptionally clear that this bill stands to create a whole new set of uncertainties that can only put Taiwan at more risk in the long term,' a senior administration official said. 'It amounts to virtually a formal defence pact. We believe this will make Taiwan less secure, not more so. Our problem is that this Congress does not care about bucking this administration on foreign policy, especially China.' The issue is complicated by statements from its proponents - including House Majority Whip Tom DeLay and Senate Foreign Relations chairman Jesse Helms - that everything the bill proposes falls within the act. Furthermore, those hawkish on China feel the time has come to clarify any 'strategic ambiguity' to scare Beijing away from Taiwan once and for all. 'Some will call this bill provocative,' said Senator Helms when he introduced it in March. 'It is true that China won't like this bill.' But Peter Brookes, the House Committee's principal adviser for East Asia, wrote in Defence News: 'The consequences of not confronting China now might mean a far more assertive Beijing in the years to come.'