Bulgaria's government resigns amid protests
The protests against soaring electricity bills have morphed into wider discontent over austerity and the way the country is being run, the official Bulgarian News Agency reported.
Parliament will vote Thursday on whether to accept the Cabinet's resignation, the government said.
If it is accepted, the president will announce an election date.
"We will perform our functions until the election of a new Cabinet and we will do everything possible to ensure continuity," Borisov said in the formal resignation letter read to parliament, according to the Bulgarian News Agency, Kazinform refers to CNN.
The government has done its best to respond to the protesters' demands, the news agency quoted Borisov as saying.
Borisov, who has been prime minister since 2009, earlier told lawmakers his GERB party would not be part of a caretaker government.
Bulgaria, a country of just over 7 million people, held its first free multiparty elections since the Second World War in 1990, according to the CIA World Factbook.