China's central bank said on Sunday it would tell banks to lower mortgage rates for existing home loans before Oct. 31, as part of sweeping policies to support the country's beleaguered property market as the economy slows.

China took steps to lower borrowing costs on as much as $5.3 trillion in mortgages for millions of families in its latest attempt to shore up the troubled property sector.

Adding to such efforts, Guangzhou city announced Sunday the lifting of all restrictions on home purchases, while Shanghai and Shenzhen said they would ease restrictions on housing purchases by non-local buyers and lower the minimum downpayment ratio for first home buyers to no less than 15%.

The People's Bank of China (PBOC) told commercial banks on Sunday to start lowering interest rates on all existing housing loans, in a sweeping move to help lighten the mortgage burden on households hit by a slowing economy.