SHANGHAI, Jan 20 (Reuters) - China lowered mortgage lending benchmark rates on Thursday as monetary authorities step up efforts to prop up the slowing economy, after data earlier in the week pointed to a darkening outlook for the country's troubled property sector.

The cut to the one-year and five-year loan prime rates (LPR) followed surprise cuts by China's central bank on Monday to its short- and medium-term lending rates, and came days after the central bank's vice governor flagged more moves ahead.

At a monthly fixing on Thursday, China lowered its one-year loan prime rate (LPR) by 10 basis points to 3.70% from 3.80%.

The cut to the 5-year rate suggested that "the Chinese authorities are keen to lower the cost of credit lending, so total credit growth is expected to rebound after the Spring Festival to ease the pressure on macro economy," said Marco Sun, chief financial analyst at MUFG.

Interest rates on medium-term lending facilities (MLF) serve as a guide to the LPR