The Principal Advisor to Lucknow Metro Rail Corporation (LMRC) E. Sreedharan has submitted his resignation citing health issues, an official said on Monday.
The LMRC has forwarded the letter to the state government for its approval.
Sreedharan, popularly known as the Metro Man, has years of experience in handling mega Metro projects in the country.
In February 2014, LMRC appointed Sreedharan as its Principal Advisor for shaping the project in the state capital.
He had played a key role in advising the maximum use of land for planning metro stations. He also advised Chief Engineers to implement austerity measures to cut expenses on maintenance and operations.
LMRC Managing Director Kumar Keshav said: "Sreedharan personally monitored the construction work of the North-South Corridor. His valuable guidance was crucial in construction of the underground section. I requested him not to resign but he said his health was not supporting him at this point of time."
Sreedharan also supervised the construction work of elevated tracks on the East-West Corridor to be built on a single pillar using lightweight technology, which brought down the total budget of the project from Rs 5,396 crore to Rs 4,538 crore (15.9%).
Earlier, Sreedharan was in the news after he wrote to Delhi Deputy Chief Minister Manish Sisodia against the free ridership scheme of the AAP government on Delhi Metro, terming it as an "election gimmickâ€ť.
The AAP later accused him of allowing himself to be used by the BJP.
In a letter addressed to Sisodia on Thursday and made public on Friday, the 'Metro Man' stressed that the free-ride scheme will have financial implications to the detriment of Delhi Metro Rail Corporationâ€™s health.
He also accused the party of playing the populist card to win women's votes in the upcoming assembly election in the state.
"I am not opposing Delhi government's proposal to bear the cost of free travel for women but objecting only to the concept of free travel in metro. If we allow free travel for women, what about more deserving categories such as students, disabled persons, senior citizens etc?" Sreedharan asked in his letter.
"No metro in the world has extended free travel facility to women exclusively. If the Delhi government is so concerned about women, my suggestion is to reimburse their cost of travel directly to them rather than allowing free travel in metro," Sreedharan wrote.
"Please remember any compensation Delhi govt. pays to DMRC is taxpayers' money and taxpayer has a right to question why only women are being given free travel. Everybody knows this is an election gimmick to win votes of women in the next assembly election," he added.