Belgium's main political parties have agreed on a plan to shut down the country's two nuclear power stations, but they have not yet set a firm date.
A new coalition government is being set up and the nuclear shutdown will be on its agenda, officials say.
If alternative energy sources are found to fill the gap then the three oldest reactors will be shut down in 2015.
Germany is the biggest industrial power to renounce nuclear energy since Japan's Fukushima disaster in March.
Belgium has seven reactors at two nuclear power stations, at Doel in the north and Tihange in the south. They are operated by Electrabel, which is part of GDF-Suez.
The agreement reached on Sunday night confirms a decision taken in 2003, which was shelved during Belgium's political deadlock following the last government's collapse in April 2010.
Belgium will need to replace 5,860 megawatts of power if it is to go ahead with the nuclear phase-out.