"Following the legislative elections last Sunday, 30 January, having heard, under the constitutional terms, the political parties represented in the new Assembly of the Republic, and taking into account the electoral results, the President of the Republic communicated to Dr. António Costa, secretary-general of the PS, his intention to appoint him as prime minister of the XXIII Constitutional Government, which will be formalised after the votes of the European and non-European constituencies have been counted," reads a note posted on the official website of the Presidency of the Republic.
In the same note, released after the head of state and the PS secretary general had begun a meeting by videoconference, it is added that "the appointment and inauguration will take place after the first session of the XV legislature of the Portuguese Parliament".
António Costa began a seven-day period of isolation on Tuesday, 1 February, after testing positive for the virus that causes Covid-19.
The PS won Sunday's parliamentary elections with an absolute majority, winning 41.7 percent of the vote and gaining 117 of the 230 seats in the national territory - with four seats from emigration constituencies still to be allocated.
Article 187 of the Constitution of the Portuguese Republic states that "the Prime Minister is appointed by the President of the Republic, after hearing the parties represented in the Assembly of the Republic and taking into account the electoral results".