The optimism of the rating agency is based on both the improved macroeconomic environment in Slovenia as well as "continued improvement in the banks' credit fundamentals", Moody's said on Wednesday.

Moreover, the agency expects "continued recovery in credit demand" that will lead to further lending growth and revenues of the three banks.

NLB and Abanka are looking at an upgrade by up to two notches, while the rating of NKBM is expected to see a two-to-three notch upgrade.

The likely upgrade will be most important for NLB in view of the upcoming privatisation of Slovenia's biggest bank, which is in the process of an initial public offering (IPO).

Slovenia committed to sell all but a controlling stake in the bank by the end of this year in exchange for Brussels approving an extensive state bailout of the bank in late 2013.

However, the government has asked the European Commission to extend the deadline, proposing to sell at least 50% by the end of 2017 and the rest by the end of 2018. A green light from Brussels is expected this month.