Thailand last tapped the international bond market in 2006 when it raised $200 million, according to data from Bloomberg. Regis Chatellier, a senior emerging markets credit strategist at Société Générale, reckoned that the government could now be looking at paying between 4 to 4.15 percent for a 10-year issue.
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While Thailand's debt management office said last month that the country could be looking to raise up to $1.5 billion in debt markets next year, the minister's comments are the first clear indication of the bigger size and long-term scope of the dollar debt plan.
Although Thailand is not seen as one of the most at risk emerging Asian economies, the debt plans come amid a worsening outlook for southeast Asia's second-largest economy.
On Monday, the central bank cut its GDP growth forecast for the country for this year to 3.7 percent. This compares to its previous estimate of 4.2 percent and is the fourth downward revision this year. Exports fell 2.9 percent last month year-on-year, the sixth straight month of decline, according to official figures also published on Monday.
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One Bangkok-based analyst said the government seemed to be seeking alternative sources of funding as insurance against local cash becoming less readily available, as the current account fell into deficit and demands grew for multibillion-dollar subsidies to rice farmers.
"They want to keep their options open, just in case domestic interest rates go up quickly and they run into liquidity problems," the analyst said.
While there is broad agreement in Thailand about the need to improve the country's stretched infrastructure, the government's proposals have been attacked by the opposition Democrats and some independent analysts. A proposed high-speed rail link is proving divisive, while some observers say the infrastructure plans as a whole lack details and should have more parliamentary oversight.