It was a flat close for the markets on expiry day. The Sensex and Nifty started in the green but saw a sharp fall in the last hour which wiped out all its gains. The key loser was the IT sector with TCS losing over 3% while banks and oil marketing companies saw gains. Markets across the world saw a poor day of trade as the US and North Korea failed to make any headway. The Nifty has now lost close to 1% in the last 3 days.