Pope Francis heads to Cyprus and Greece on Thursday for a five-day trip intended to strengthen ties with the Orthodox Church and highlight the plight of migrants with a return trip to Lesbos.

Just weeks from his 85th birthday, months after undergoing colon surgery in July and despite the rapidly changing coronavirus situation in Europe, the pontiff is back on the road to push two of the priorities of his papacy.

The first stop is Cyprus from December 2-4, followed by two days in Greece -- both countries with an Orthodox majority that are home to tens of thousands of Catholics.

The 4,500-kilometre round-trip will include a dozen speeches and various meetings with political and religious leaders, including Greece's top cleric, Archbishop Ieronymos.

In a highly symbolic moment, Francis will also return on December 5 to the island of Lesbos, a key gateway for migrants into Europe where he famously declared in April 2016: "We are all migrants."

At the time, Europe was facing a huge influx of migrants from Syria.

But it remains a tragically live issue today, from the recent drownings in the Channel to the escalating situation at the border between Belarus and Poland, where migrants desperate to reach Europe have been trapped in squalid, freezing conditions.

The pope is expected to again call the world's attention to the migration crisis, which he has called "the worst humanitarian catastrophe since World War II".

In Lesbos, the pope plans to make "a humanitarian statement, not a political statement", Josif Printezis, the archbishop of Greece's Aegean islands, told AFP.

"He wants to raise awareness among European citizens about the issue of refugees, because the Mediterranean is full of drowned people."

Francis' return to Lesbos represents "a very strong message" especially since "the situation has worsened", said Roberto Zuccolini, spokesman for the Italian lay Catholic association Sant'Egidio, which has been helping migrants in Europe since 2015, particularly in Greece.

"The pope intends to remind all of Europe in a strong way that it has a common responsibility," Zuccolini said.

Francis will return to Lesbos, a key gateway for migrants into Europe where he famously declared in April 2016: 'We are all migrants.'
Francis will return to Lesbos, a key gateway for migrants into Europe where he famously declared in April 2016: 'We are all migrants.' POOL via AFP / Filippo MONTEFORTE

The visit to Athens will also focus on dialogue with Orthodox Christians, who are upwards of 300 million strong in the world. The Orthodox Church split from the Catholic Church in 1054.

Two meetings are planned with Greek Orthodox leader Ieronymos.

"The pope wants to strengthen ties with the Orthodox community," Vatican expert Marco Politi told AFP, adding that that "gestures of brotherhood" from the pope had increased.

He cited Francis' 2014 request to Patriarch Bartholomew I of Constantinople, asking the spiritual leader of Orthodox Christians to bless him.

The first stop is Cyprus, where the pontiff is expected to deliver "a plea for unity and peace", said a Vatican source.

The Mediterranean island has been divided since 1974. In the south is the Republic of Cyprus, a member of the European Union, and over the border the self-proclaimed Turkish Republic of Northern Cyprus (TRNC), which is only recognised by Ankara.

Negotiations to end the impasse stalled in 2017.

In the capital Nicosia, cut in two by a UN-administered buffer zone, the pope will be received by President Nicos Anastasiades and Archbishop Chrysostom II, primate of the local Orthodox Church.

On Friday, he will celebrate a Mass at a stadium in front of 7,000 people, and an ecumenical prayer with migrants near the "green line" separating the city in two.

It will be the pope's 35th international trip since becoming pope in 2013 and comes just weeks after his last, to Budapest and Slovakia.

He also made a historic trip to Iraq in March after which he confided that he felt "much more tired" than during previous trips.

However, he announced he intended to continue his travels in 2022, especially in Oceania.