Replying to a nearly half-day debate on the Feb 25 railway budget, Banerjee said the work of the railways should go on unhindered irrespective of whether she was the minister or not.
This was seen as an indication of her future moves in case her party, the Trinamool Congress, wins the West Bengal assembly elections.
Touted to become the state chief minister if the Trinamool Congress ousts the Left parties in the state, Banerjee said: "I may remain tomorrow or not (as the railway minister). Somebody else may come and take over... but there has to be some system for proper rail services. We have to do it."
Combative as ever, Banerjee also countered the attacks of her detractors that she was announcing railway projects for West Bengal that had no Planning Commission approval.
"I have not done anything without the approval of Planning Commission. I will do it within the norms and not outside the norms of the Planning Commission and constitution.
Anybody can have differences of opinion with me on my policies, but they should not play politics with development," she said.
Banerjee said railways was one field in which India could do better and help the economy to grow faster.
She also objected to the Bharatiya Janata Party (BJP) attacking her on what it termed as her Bengal-centric railway budget. "It is not correct. I do not agree with this," she said.
The minister said she had "the heart to give more" rail lines, train services and stoppages as per the request of the MPs, but there was no scope for more when the available resources were looked at.
The house witnessed a minor clash between the lawmakers of her party and Left MPs over an alleged suicide attempt by a youth outside Banerjee's residence in Kolkata because he was denied a job in railways after being promised one.
Trinamool MPs strongly objected to CPI-M member Ramchandra Dome's allegation. Senior Trinamool leader Sudip Bandopadhyay said the Left MP was anti-Bengal.
Reacting to the allegation, the minister denied the incident took place. "This is absolutely concocted and false. He can speak anything about the railways but this allegation is totally wrong," an angry Banerjee shouted.
Earlier in the pre-lunch session, the house witnessed two adjournments after Samajwadi Party members forced disruption during the question hour over the alleged "house arrest" of their leader Mulayam Singh Yadav and his son Akhilesh in Lucknow ahead of their agitation against Uttar Pradesh's ruling Bahujan Samaj Party.
Soon after the house paid homage in the morning to Congress leader Arjun Singh, who died Friday, Samajwadi Party members rushed towards the chair and raised slogans demanding the dismissal of the Uttar Pradesh government.
Lok Sabha Speaker Meira Kumar's requests to the protesting members to return to their seats went unheeded, forcing her to adjourn the house twice.
Rajya Sabha also mourned the death of Arjun Singh who was a sitting member, with chairman Hamid Ansari saying the country had lost "an eminent administrator and a distinguished parliamentarian." The upper house adjourned for the day soon after as a mark of respect for the departed leader.