Party members are to choose a replacement for Pedro Passos Coelho, the former prime minister who announced last week that he would not be standing again, following poor local election results on 1 October, on 13 January. The congress is then to take place from 16 to 18 February.

The announcement was made by the PSD's secretary-general, José Matos Rosa, after a meeting of the National Council late on Monday night. He said that it had been approved "by an overwhelming majority".

The meeting had considered an alternative proposal under which the leadership election would be held on 9 December and the party congress in January.

In line with party statutes, if there are more than two candidates in the race and neither obtains more than 50% of the vote in the first round, there is to be a second. That would now take place on 20 January.

Matos Rosa also announced that 2 January had been set as the deadline for candidates to throw their hats into the ring and submit motions on overall party strategy. The electoral campaign is to run from that date until 12 January.

The deadline for party members to pay their membership fees so as to secure a vote in the contest, and the choice of delegates for the congress is 15 December.

So far only Rui Rio, a former mayor of Porto, has publicly said he is standing for the leadership, but Pedro Santana Lopes, a former prime minister, is widely expected to announce soon.