Pope Francis has met a Colombian nun who was freed on Saturday by Islamists in Mali after more than four years as a hostage, a Vatican spokesman has said.

After travelling to Rome, Gloria Cecilia Narváez met the Pope on Sunday before the celebration of a Mass.

The nun was taken hostage in 2017 while working as a missionary in Koutiala, about 400km (248 miles) east of Mali's capital Bamako.

It is not clear whether a ransom was paid to secure her release.

The office of Mali's president said the nun's release had come after more than four-and-a-half years of "combined effort of several intelligences services".

It also praised her for "courage and bravery".

Sister Gloria, 59, said on state TV she was grateful to Malian authorities "for all the efforts you've made to liberate me".

She added: "I am very happy, I stayed healthy for five years, thank God".

The Archbishop of Bamako, Jean Zerbo, also thanked "Malian authorities and other good people who made this release possible."

There had been irregular reports of her safety over the years. Earlier this year, two Europeans who managed to escape captivity reported that she was well.

In March, her brother received a letter from her confirming she was still alive. He told AFP news agency earlier this year that the note had been written in block capitals "because she always used capital letters", and contained the names of their parents, ending with her signature.

Mali has been struggling to contain a growing Islamist insurgency that first emerged in the north of the country in 2012. Kidnappings in particular have become more common in the former French colony as the security crisis has deepened.

According to a non-governmental organisation, Armed Conflict Location and Event Data Project, more than 935 people have been abducted in the country since 2017.

However, Colonel Assimi Goita, who led a military coup that removed the country's civilian government last year, has sought to assure Malians and the international community that efforts are under way to secure the release of all those still being held.

French troops have been leading operations against Islamist groups in the region since 2014, however President Emmanuel Macron announced in June that operations would be reduced over the coming year.

This has reportedly led to the Malian government turning to the Russian mercenary collective, the Wagner group, for assistance. The secretive group has been involved in conflicts across Africa, including fighting with a rebel general, Khalifa Haftar, in Libya.