Portugal's foreign ministry summoned Iran's ambassador on Tuesday to condemn Saturday's attack on Israel by Tehran and to demand the immediate release of a Portuguese-flagged container ship, the MSC Aries, that was seized by Iran on April 13.
The ministry said in a statement after the meeting that it "will await the results of this formal measure and evaluate any additional steps, depending on those."
It said Portugal had demanded the release of the crew "as explanations provided so far have not been considered consistent," and urged de-escalation in the Middle East.
Tehran said on Monday that Iran's Revolutionary Guards seized the cargo vessel - allegedly linked to Israel - in the Strait of Hormuz for "violating maritime laws."
Barrage of missiles
Iran launched a barrage of missiles and explosive drones on Saturday in an attack that Tehran said was self-defense after a suspected Israeli strike on its consulate in Damascus on April 1.
MSC, which operates the Aries, has said it is working "with the relevant authorities" for the vessel's safe return and the wellbeing of its 25 crew.
MSC leases the Aries from Gortal Shipping, an affiliate of Zodiac Maritime. Zodiac is partly owned by Israeli businessman Eyal Ofer.