The privatisation agency extended until April 29 the deadline for submitting binding offers for the freight unit of the country's railway holding company BDZ at the request of the participants in the tender.
The agency's decision comes amid mounting public pressure to put on hold the deal until after the snap elections in May.
Earlier this month the deadline, which originally expired on March 12, was pushed forth to March 28.
The deadline for submitting deposits for participation in the tender too was extended - until April 26, the agency said.
Last month the privatisation agency admitted four candidates - Romania's Grup Feroviar Roman, Sofia-based Bulgarian Cargo Express and Balkan Financial Services, and Austria's Donau-Finanz Transport und Beteiligung - to the next stage in the tender for 100% of BDZ's freight unit.
The government aims to get at least 200 million levs ($133.66 million/102.3 million euro) from the sale of the freight unit of BDZ, former transport minister Ivailo Moskovski said in January.