LISBON (Reuters) - Nearly 70% of Portuguese voters want an early election following the abrupt resignation of the Socialist prime minister, a survey showed on Thursday, as President Marcelo Rebelo de Sousa was due to announce his decision on the matter later in the day.
Antonio Costa stepped down on Tuesday after prosecutors detained his chief of staff in an investigation into alleged illegalities in his government's handling of lucrative lithium and hydrogen projects.
Prosecutors said Costa was also the target of a related probe. He has denied wrongdoing.
It is up to the conservative president to decide whether to allow the Socialist Party (PS), which has a parliamentary majority, to form a new or interim government, or to dissolve parliament and call an election.
His office said he would address the nation after meeting his consultative body, the Council of State. The meeting starts at 3 p.m. (1500 GMT).
A survey by Intercampus for newspapers Jornal de Negocios and Correio da Manha showed 67.8% of voters would prefer an early election, while 25.7% would rather see PS pick a new premier and form a government.
Analysts also see an election as the most likely option, although Rebelo de Sousa could choose to give more time to the PS to get next year's budget, already approved by parliament on first reading, over the line in parliament.
Joao Duque, dean of the Lisbon School of Economics and Management, said the president was likely to take into consideration Europe's volatile economic situation and allow lawmakers to vote on the budget bill, scheduled for Nov. 29.
PS President Carlos Cesar said on Wednesday that if the president decided to call an election, March would be the best timing. Other parties pointed to January or February.
The budget includes lower income tax rates for the middle class, higher wages and social benefits.
Separately, those detained in the investigation, including Costa's close friend and consultant Diogo Lacerda Machado, were due to appear before a Lisbon court on Thursday. They were suspected of crimes of corruption and influence-peddling, prosecutors said.
(Reporting by Catarina Demony, Patricia Rua, Sergio Goncalves, editing by Andrei Khalip and Alex Richardson)