S&P, which already issues ratings on international and local currency scales, released ratings for 19 of the regions best-known banks and companies on its new Asean scale, which runs from axAAA to axC.
Tom Schiller, executive director at S&P, said the initiative had been driven in part by the general secretariats and finance ministers efforts to promote Asean both as an integrated financial market and as an asset class.
The new ratings sit alongside S&Ps existing global scale and are designed to allow investors to compare bonds across the Asean region, regardless of the currency. Singapores DBS Bank is rated axAAA, and Bangkok Bank of Thailand is rated axA+.
S&Ps scheme, the first of its kind, was launched on Sunday as finance ministers reaffirmed their commitment to economic integration by 2015.
Korn Chatikavanij, finance minister for Thailand, the current chair of the ASEAN group, told an investor seminar in Bali: We shall make every effort to ensure the delivery of the roadmap for financial integration that is consistent with the promise of a progressive and prosperous ASEAN community by 2015.
By that time, there will be free movement of goods, services, investment, skilled labour, freer flow of capital and equitable economic development, Chatikavanij pointed out.
The S&P pilot project will compare fixed income instruments across the region and issue ratings based on their relative risk of default, with a target of rating 500 borrowers in the region by 2015.
Surin Pitsuwan, Asean secretary general, welcomed the initiative, which he said would show the quality of Asean assets to international investors.
But bankers were sceptical that the move would have an immediate impact. Frank Kwong, head of Asian debt syndicate at BNP Paribas, said it was a positive step, but that capital controls and tax concerns still prevented international investors from getting involved in cross-border deals.
Investors are already comfortable with credit risk, Kwong said. It needs more of a push to develop access. Very few bonds sold in Asean currencies go to international investors.
Calls for closer regional integration have intensified in light of the global financial crisis. Ray Ferguson, chief executive for Southeast Asia at Standard Chartered in Singapore, said: The crisis has given [integration] more impetus.
When everyone individually is doing well there is less incentive to do the hard work. The volatility means more pragmatic conversations can happen.
But ministers ruled out the possibility of speeding up progress towards an integrated Asean market, which has a target date of 2015.
Rosalia de Leon, undersecretary in charge of international finance for the Phillippines, told investors on Saturday: In this current environment it might be difficult to accelerate anything.