Ms Haigh, who is also the Shadow Secretary of State for Transport, hit out at her opposite number Grant Shapps during an address in the House of Commons.
Sheffield and Rotherham will see reductions first from July 24 and further cuts are expected when Covid-19 grants end in October.
She said the industry in South Yorkshire was facing a ‘cliff edge’ and that ministers were overseeing managed decline.
Mayor Oliver Coppard has called for government intervention of £85 million over the next three years.
He also called on government to give South Yorkshire Mayoral Combined Authority (SYMCA) more control over how the buses run in South Yorkshire.
Right now, private companies run the buses and keep the profits, while SYMCA have little or no control over where those buses go, or how much they charge
Speaking in Parliament on Thursday (June 30), Heeley MP Haigh said: “Buses are a lifeline for so many people and during the pandemic they were there to support key workers and get them to our hospitals and supermarkets. The government provided funding at that point, and it meant that much needed services could continue to run.
“The industry is now facing a cliff edge and if further funding is not provided then we could see many services disappear for good.
“We already know that bus companies have said that a third of services could be cut by July in South Yorkshire alone and from October South Yorkshire could be left with only four buses running across the region after 10pm.
“We’re facing a climate emergency, and this is the time that we should be investing in our bus services and making them reliable, accessible and affordable.
“The government needs to start putting the needs of our communities first and investing in the transport that they use daily to get to work, for leisure and to see family.
“They talk about levelling up but at the moment they are delivering a managed decline.”