TOKYO, April 1 (Reuters) - Japan's benchmark 10-year government bond yields (JGB) fell to a two-week low on Friday, after the central bank pledged to ramp up scheduled bond purchases in the second quarter.

The 10-year JGB yield fell one basis point to 0.200%, its lowest since March 18.

In a closely-watched bond buying schedule for April-June, the Bank of Japan (BOJ) said on Thursday it would increase purchases for government bonds across the yield curve compared with the current quarter.

The announcement came after the BOJ maintained its offer to buy unlimited amounts of 10-year bonds at a fixed rate of 0.25% for four straight days this week, after the key yield hit the bank's target limit.

Yields on other notes also retreated, with the 20-year JGB yield falling four basis points to 0.660% and the 30-year JGB yield falling six basis points to 0.870%.

The two-year JGB yield fell one basis point to minus 0.040% and the five-year yield fell 1.5 basis points to 0.010%.

The 40-year JGBs have not been traded and the yield remained at 0.975%.

Benchmark 10-year JGB futures rose 0.17 point to 149.87, with a trading volume of 9,145 lots. (Reporting by Junko Fujita; Editing by Rashmi Aich)