Lewisham East's Labour MP Heidi Alexander hands in the petition against plans to close Lewisham's Accident and Emergency Department to Downing Street.
Labour MP for Lewisham East Heidi Alexander said: "Undoubtedly we have a really big fight on our hands to reverse these proposals. Ultimately it's a decision for Jeremy Hunt, the Secretary of State for Health. He will take that decision in February.
"But with 32,186 signing our petition in just five weeks. I think it's a very clear demonstration about the concern and opposition that exists in Lewisham about the downgrading closure of the A&E."
Consultants and MPs opposed to plans to close Lewisham's Accident and Emergency department have handed letters and a 20,000-signature petition to Downing Street.
Protesters, including Lewisham East MP Heidi Alexander, say the closure would leave them with one accident department for 750,000 residents.
The planned closure is part of a reorganisation aimed at saving the South London Healthcare Trust after it went into administration.
A petition with over 21,000 signatures opposing plans to close Lewisham's Accident and Emergency Department will be handed in to Downing Street later.
Protestors have demonstrated against the closure in recent weeks.
The MP for Lewisham East, Heidi Alexander, will join doctors and consultants to deliver the document and other letters.