"We will give what is needed to convince the ICC that Libya is capable of conducting a fair trial in accordance with international standards," the state Lana news agency quoted Justice Minister Salah al-Marghani as saying on Sunday.
Libya has challenged the ICC's right to put al-Islam on trial on the grounds that since it is planning its own proceedings, the international court in The Hague had no jurisdiction because it should intervene only if the local legal system is not up to the task.
"Libya will appeal the decision … A team of Libyan and international experts is working on preparing the appeal," al-Marghani was quoted as saying.
Few expect Libya to surrender Saif al-Islam Gaddafi to the ICC, which wants to try him for alleged crimes committed during the 2011 uprising that toppled his father.
ICC judges on Friday rejected Libya's position, saying Libyan government lawyers had not proved their authorities were investigating the same crimes as the international prosecutors.
Full custody over al-Islam
They also questioned whether Libya had full custody over al-Islam, something they would need if they were to try him. The British-educated 40-year-old is in the custody of his rebel captors in the western mountain city of Zintan, where the Libyan government's authority is weak.
Saif al-Islam was a powerful figure in his father's government and has been accused of orchestrating brutal reprisals against anti-Gaddafi protesters.
Libya's new rulers are keen to try Gaddafi loyalists at home to show the country's citizens that those who helped Gaddafi stay in power for 42 years are being punished. Human rights activists worry that a weak government and rule of law in Libya may mean that legal proceedings there will not meet international standards. – Reuters