SHANGHAI/SINGAPORE, March 20 (Reuters) - China left benchmark lending rates unchanged at a monthly fixing on Wednesday, in line with market expectations, after the central bank kept a key policy rate steady last week amid some signs of improvement in the broad economy.

The one-year loan prime rate (LPR) was kept at 3.45%, while the five-year LPR was unchanged at 3.95%.

In a Reuters poll of 27 market watchers conducted this week, all respondents expected both rates would stay unchanged.

Most new and outstanding loans in China are based on the one-year LPR, while the five-year rate influences the pricing of mortgages. (Reporting by Winni Zhou and Tom Westbrook; Editing by Muralikumar Anantharaman)