SHANGHAI, Jan 25 (Reuters) - China stocks opened steady on Thursday after the country's central bank announced a deep cut to bank reserves the previous day to support a fragile economy and tumbling share markets.

The 50-basis points (bps) cut by the People's Bank of China (PBOC) - the biggest in two years - in the amount of cash banks must hold as reserves will inject about $140 billion of cash into the banking system.

China's blue-chip CSI300 Index was almost flat, while Hong Kong's Hang Seng benchmark was down a touch by 0.1% at GMT 0145.

(Reporting by Shanghai Newsroom Editing by Shri Navaratnam)