Citigroup has tapped into Greece's privatisation programme for the second time this year with the mandate to sell a stake in the National Bank of Greece (NBG).

The Greek ministry of finance will offer 10% of the ordinary shares in NBG, which is expected to equate to about 25.5 million shares, to institutional investors. The offering, which represents around a quarter of the state's stake in NBG, is taking place via an accelerated bookbuilding process. The deal is worth around €490m ($579m) and will price on Thursday. NBG will be subject to a 180-day lock-up after the share placing.