Sources familiar with the matter were quoted by Reuters as saying that the Amsterdam-based company has planned to offload the 31% stake in the lender, as it gears up to repay to the creditors, who bailed out the beleaguered firm during the financial crisis of 2008.
Following the completion of elections to determine a new Malaysian government next month, the auction is likely to see participation from lenders that include CIMB Group and Malayan Banking.
The sale process is also likely to draw interest from many Japanese, Chinese and South Korean financial enterprises, the sources told the news agency.
It is also believed that the disposal of 31% stake by ING, will further spark the full sale of TMB, which has a market value of $3.8bn.
According to the current financial regulation of Thailand, foreign lenders do not need to obtain central bank approval for acquiring up to 25% stake in a Thai bank.
A foreign firm will have to seek permission from the Thai central bank if it plans to purchase up to 49% stake in a bank, while more than 49% requires approval from the Thai government.
ING has appointed the US-based JP Morgan as financial adviser to select a suitable buyer for the stake in TMB Bank, the sources said.
In 2007, the Netherlands-based company purchased the stake in TMB, formerly known as Thai Military Bank, for €460m, in which it holds 25.2% directly and 5.84% though non-voting depository receipts.