Authorities in Gibraltar have released the Iranian oil tanker, the Grace 1, at the centre of a diplomatic dispute between Tehran and London.
It was not immediately clear why the Gibraltar court had ordered the ship to be released.
Earlier on Thursday, the US government applied to officially seize the ship from Gibraltar control.
The Grace 1 was seized by Royal Marines last month, as the UK claimed it was aiming to deliver oil to Syria, in violation of EU sanctions.
Gibraltar’s chief minister Fabian Picardo reportedly lifted the detention order and said the government has received “formal written assurances” from the Iranian government that the ship will not discharge its cargo in Syria, according to local newspaper the Gibraltar Chronicle.