Aminatou Haidar has been on hunger strike at Lanzarote airport, in Spain's Canary Islands, since being blocked from entering Morocco on 15 November.
She has been nicknamed the "Gandhi of Sahara" after seeking independence for a disputed region of Western Sahara.
Morocco controls the Western Sahara but many there want self-determination.
Moroccan officials confiscated Ms Haidar's passport when, on returning from Lanzarote after collecting a prize, she refused to state her citizenship as Moroccan.
'Weak condition'
Abderraham Leibek said Ms Haidar voluntarily handed over her passport and would be pardoned - and a new passport provided - if she apologised.
"When a Moroccan carries out an act of treason against her homeland, the only way in which Morocco - the Moroccan government - will pardon her is if she apologises," he said in comments on Spanish television.
Ms Haidar completed her 17th day of hunger strike on Wednesday. She has been surviving on sweetened water.
She has vowed to carry on refusing food and has said she is prepared to die if she cannot return home.
She refused an offer of Spanish nationality offered to her on Saturday in an attempt to end the deadlock.
Instead, Ms Haidar, who is camped outside Lanzarote airport, has demanded her original passport back and refuses to ask for another one.
Supporters say Ms Haidar, who won the Robert F Kennedy Human Rights Award last year, is in a weak condition.
Morocco annexed Western Sahara in 1975 after Spain withdrew from the territory.
Africa's last colonySince 1975, three quarters of the Western Sahara territory has been illegally occupied by Morocco. The original population lives divided between those suffering human rights abuses under the Moroccan occupation and those living in exile in Algerian refugee camps. For more than 40 years, the Saharawi await the fulfilment of their legitimate right to self-determination.
Since 1975, three quarters of the Western Sahara territory has been illegally occupied by Morocco. The original population lives divided between those suffering human rights abuses under the Moroccan occupation and those living in exile in Algerian refugee camps. For more than 40 years, the Saharawi await the fulfilment of their legitimate right to self-determination.
