In a letter to Union Minister for Housing and Urban Affairs Hardeep Singh Puri, Mr Kejriwal today said the proposed hike, to be effected from October 10, would be in violation of the recommendations of the fare-fixation panel.
"The fare-fixation committee had recommended a gap of one year between two fare hikes. This recommendation is being completely violated because the proposed second hike in October, 2017 will take place even before six months since the previous fare hike," he said.
The committee, comprising representatives of both the state and the Centre, which have equal stakes in the Delhi Metro Rail Corporation (DMRC), is entrusted with recommending fare hikes.
The Delhi Metro fares were last revised in May. If the hike is effected, the fares will go up by a maximum of Rs 10 from October 10.
The existing fare structure is: up to 2 km -- Rs 10, 2-5 km -- Rs 15, 5-12 km -- Rs 20, 12-21 km -- Rs 30, 21-32 km -- Rs 40 and for journeys beyond 32 km -- 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.
"The chief minister has pointed out that the residents of Delhi are still reeling under the impact of the previous steep fare hike by the DMRC in the month of May and the proposed second fare hike from 10th October will be simply unacceptable in this time of economic distress," an official statement quoted Mr Kejriwal as saying.
The Aam Aadmi Party (AAP) chief urged Mr Puri to use his official capacity under section 86 of the Delhi Metro Railway (Operation and Maintenance) Act 2002 and issue directions to the metro officials, asking them to put the fare hike on hold.
He also demanded that a board meeting of the DMRC be convened to review the decision.
The AAP has threatened to launch protests against the proposed fare hike. A delegation of AAP MLAs is scheduled to meet DMRC chief Mangu Singh on Monday with a demand to put the decision on hold.
The Delhi Metro, on its part, has been maintaining that it has a "huge loan liability" and a rapidly rising operating ratio, which means its expenditure as against every rupee earned is going up.
According to the DMRC, the operating ratio, which was Rs 55 in 2008-09, went up to Rs 74 in 2016-17 due to a rise in the energy, staff and repair or maintenance costs.
While the cost for energy has increased from Rs 3.21 per unit to Rs 6.58 per unit, staff cost from Rs 1.17 crore per km to Rs 2.80 crore per km and repair and maintenance cost from Rs 1 crore per km to Rs 3.13 crore per km, as per a DMRC report.
"As on March 31, 2017, DMRC has taken a loan of Rs 26,760.28 crore from JICA (Japan International Cooperation Agency) and re-paid only Rs 3770.79 crore (interest of Rs 2263.67 crore and repayment of a principal amount of Rs 1507.12 crore) till March 31," according to the report.
In his letter, Mr Kejriwal referred to the financial model of the Hong Kong Metro and suggested that following it would significantly improve DMRC's finances and lead to a much lower fare hike.
He also mentioned that his assertion was based on the "advise" of the fare-fixation panel.
"The fare-fixation committee has advised the DMRC to raise funds through real estate development from the large number of properties allotted to it by the government. If this is done efficiently and transparently, the resultant income will help reduce the fare of the ordinary commuter, as in the case of the Hong Kong Metro," the statement quoted the chief minister as saying.