The state currently owns 45.3 percent of TeliaSonera, 19.9 percent of Nordea and 6.8 percent of OMX. The government did not say when it would sell the stakes, nor whether it would sell all or just part of its holdings.
The three other companies are the wine and spirits manufacturer Vin och Sprit, real estate company Vasakronan and the mortgage lender SBAB, which are all 100 percent owned by the Swedish state.
All six companies “are active in markets that are entirely commercial and which are characterized by a functioning competition,” a joint statement from Financial Markets Minister Mats Odell and Industry Minister Maud Olofsson said.
The centre-right government, which came to power after ousting the Social Democrats in September general elections, had announced a vast privatisation programme as part of its election platform.
The Swedish state has majority or minority stakes in 57 companies which together employ 200,000 people.
The first wave of privatisations is expected to bring 100 billion kronor (11 billion euros, 14.5 billion dollars) to government coffers during the next two years.
After selling holdings in listed companies, the government also plans to sell state-owned shares in non-listed groups, such as the electricity company Vattenfall.
The government on Thursday also announced plans to deregulate the country’s 35-year-old pharmacy monopoly by January 2009.