Rabat - Morocco's government said the Dutch "abortion boat", due to arrive on Thursday in the first such trip to a Muslim country, is not authorised to act and must be prevented from doing so.
Women on Waves, the Dutch group organising the trip, said earlier that the ship, which is equipped to provide women with the medication needed for "safe legal medical abortions" up to six and a half weeks into pregnancy, would arrive at 13:00 GMT on Thursday.
It was due to land at Smir, on Morocco's Mediterranean coast, about 40km east of Tangier.
In the first official response to the planned visit, the health ministry on Wednesday urged the relevant authorities to prevent the visit from taking place.
"The ministry of health... has never been informed of this event and has not authorised any non-resident party or doctor in Morocco to carry out this medical intervention," it said in a statement.
"The ministry calls on the relevant authorities to do what it is necessary to ensure that the law is applied," it added.
Moroccan law prohibits abortion, except when the life of the mother is in danger.
Women on Waves said the purpose of the visit was to provide abortions to women that might otherwise be exposed to grave health risks, and planned to set up a hotline to inform women about how to induce medical abortions safely at home.
Doctor Rebecca Gomperts, the Dutch group's founder, told AFP that around 600 to 800 Moroccan women have an abortion every day.
"The problem is that only about 200 cases are done properly, by women who have money," she said, with the rest resorting to dangerous methods because they are unable to afford the more expensive treatment.
This leads to the deaths of 78 Moroccan women each year on average, Gomperts claimed, citing statistics provided by the World Health Organisation.
In the past 11 years, a Women on Waves ship has visited Ireland, Poland, Portugal and Spain, sparking protests in each country from pro-life groups.
Ordinary Moroccans on Wednesday voiced strong opposition to the visit, which local youth group the Alternative Movement for Individual Liberties (MALI) has helped to organise.
"Moroccan law forbids abortion. Moroccan religious identity says it is forbidden and so does Islam. So the government cannot allow this ship to come to Morocco," lawyer Abdelmalik Zaza was quoted as saying in Al-Tajdid, the newspaper of ruling Islamist party the PJD.
Hannan Idrissi, a member of a Moroccan pro-life group, said the abortion figures given by Gomperts were incorrect, and disputed the motives of the MALI youth group.
"The Mali movement that invited the ship is known for its disrespect for ethics and the dignity of Moroccan society," she was quoted as saying by Al-Tajdid.