The source said Puri suggested such a provision since operational loss is the responsibility of the state government as per the metro guidelines.
Kejriwal had written to the Housing and Urban Affairs (HUA) Ministry to issue a direction to Delhi Metro Rail Corporation (DMRC) to put on hold the proposed hike in fares, as recommended by 4th Fare Fixation Committee (FCC).
In response, the source said, Puri in a letter to the chief minister yesterday said, "Your suggestion that this ministry direct that the fare increase be kept on hold overlooks the fact the central government does not have any such authority. Tampering with the recommendations of FFC is legally untenable."
The source said Puri also annexed with his letter a written response from DMRC which said "The Committee's (FFC) recommendations are binding on the Metro Rail Administrations as per provisions of Section-37 of this Act (Metro Act).
"Neither the Central Government nor the State Government or even the Board of the Company has legal power to change the recommendations made by the FFC."
Noting that it would be "wrong to claim" that there were two increases in fares in a short period of five months, Puri said the 4th FFC itself recommended the fare hike, coming after a gap of seven and a half years, to be implemented in two instalments -- one in May and another in October, the source added.
Regarding a cap on fare hike, Puri said it would be "incorrect to apply" the cap of seven per cent annual fare rise, as the latest increase in fare was done after seven and a half years, the source added. The last revision of fares were done in 2009.
Fares will go up by a maximum of Rs 10 after the latest hike comes into effect.
The existing fare structure is: up to 2 kms -- Rs 10, 2-5 kms -- Rs 15, 5-12 kms -- Rs 20, 12-21 kms -- Rs 30, 21-32 kms -- Rs 40 and for journeys beyond 32 kms -- Rs 50.
From October 10, for a distance of up to two kilometres, the fare will remain Rs 10, but for a distance between two and five kilometres, it will go up from Rs 15 to Rs 20.
For the subsequent slabs, it will go up by Rs 10 each, which means the maximum fare will be Rs 60.