The Singapore Government is refusing to lift the veil of secrecy it has drawn over its billions of dollars of state investments around the world, saying confidentiality is an essential prop in its defence of the Singapore dollar. Monetary Authority of Singapore (MAS) chairman Lee Hsien Loong justified this stance yesterday as the de facto central bank made the rare disclosure that it had intervened to support the Singapore dollar last week. The Government of Singapore Investment Corp (GIC) manages more than US$100 billion of the country's reserves. Annual returns on its holdings are not published despite calls from some Singapore citizens and opposition politicians. Mr Lee, who is also the deputy prime minister, told parliamentarians during Question Time that revealing more details of GIC's activities would hand an advantage to currency speculators. 'The reserves of the government, including the reserves managed by GIC, are an important factor in maintaining confidence in the Singapore dollar,' Mr Lee said. 'Market players . . . do not know the exact amount that we have invested abroad and in what assets. Publishing this information would make it easier for would-be speculators to assess their chances and plan their attacks and this is not in the public interest.' The MAS chairman parried opposition suggestions that such secretiveness was undemocratic. 'The government governs as it judges wise and best and it has to stand up and defend its judgment,' Mr Lee said. 'It does not stand up and say here are all the things, here are all the data, here are my national secrets, here are defence secrets, here are my foreign policy moves and here are my innermost reserves. No government in the world does that.' The verbal fire-fight came as the MAS admitted it sold US dollars last week to strengthen the Singapore dollar, which has been trading at 11-year lows. The intervention was in line with present policy of seeking a gradual and modest appreciation of the Singapore unit against a trade-weighted basket of leading currencies. Foreign exchange analysts say the Singapore dollar has been losing ground against the greenback because of the economic slowdown and hefty overseas acquisitions planned by Singaporean companies. The Singapore dollar closed yesterday at S$1.8125 per US dollar. It ended last year at $1.7365 to the greenback. The tightening stance by the MAS - which manages the exchange rate as its principal tool to quell inflationary pressures - has surprised some economists, who have said a looser policy would be more appropriate. The performance by the GIC - which is headed by Senior Minister Lee Kuan Yew - is checked by the auditor-general, accountant-general and council of presidential advisers but their findings are not released. The senior minister recently said: 'It is not in the people's interest, in the nation's interest, to detail our assets and their yearly returns. There is total accountability.'