Prince Charles will make a historic visit to Greece as the UK deploys one of its strongest “strategic resources” to improve bilateral relations against a backdrop of increasingly complex Brexit negotiations.

The royal charm offensive, which begins when the prince and the Duchess of Cornwall fly into Athens on Wednesday, is officially aimed at highlighting the two nations’ longstanding maritime and military links.

But the prince also signalled the three-day tour could heal a wound that goes back decades. Expressing rare public emotion for “the very special country” that is his father’s birthplace, the future king said he had long harboured a love for Greece.

“Apart from anything else, Greece is in my blood and I have long had a fascination for her ancient culture and history,” he told the conservative Greek daily Kathimerini, in comments published on Tuesday. “I have been so fortunate to have visited some of Greece’s many beautiful and unique places.”

Prince Andrew of Greece, the father of Prince Philip. Photograph: Keystone/Getty Images

Greece is among the few nations – and the only EU member state – not to have been officially visited by the Queen. The Duke of Edinburgh, born a Greek prince on the island of Corfu, was forced to flee after the Asia Minor disaster in 1923, with his own father, Prince Andrew, only narrowly avoiding being sentenced to death and shot. Relations soured further when the Greeks voted to oust the monarchy, unceremoniously toppling King Constantine in a controversial referendum in 1974.

The fraught history has long been attributed to the royal family’s official frostiness towards Greece.

“As the heir apparent, Charles’s visit can ease the tensions on the part of a family aggrieved by Greece deposing one of their own,” said Prof Kevin Featherstone, who heads the Hellenic Observatory at the London School of Economics. “Constantine is an intimate of the British royal family, but even he has come to terms with the reality,” he told the Guardian. “Now we need Buckingham Palace to do the same.”

The tour – part of a five-day official visit to France and Greece, undertaken at the request of the British government – ends a 45-year hiatus since the two countries last exchanged state visits.

As preparations were being finalised, presidential palace officials said the couple, who will spend 48 hours in Athens before flying to Crete on Friday, could expect “star” treatment. The prince, who turns 70 this year and has increasingly assumed his mother’s overseas duties, will be received as head of state in all but name.

“With the exception of a ceremonial guard outside the palace it will be a state visit in every other way,” one aide said. “Charles will meet the president and prime minister, a state dinner will be held in his honour and he will lay a wreath at the Tomb of the Unknown Soldier.”

With bilateral ties acquiring ever more significance in the face of Britain’s looming exit from the EU, the prince is seen as a powerful national resource, UK diplomats said. “The gain is in the goodwill reflected in those who get to meet their royal highnesses,” said Capt Tim Ferns, the defence attaché at the British embassy in Athens.

“We are deploying a powerful strategic resource. The effect is impossible to measure … it’s neither soft power nor cultural influence, but what we do know is that it works, strengthening our friendships and building relationships.”

Prince Charles has visited the monastic community of Mount Athos in Greece many times. Photograph: Dimitris Sotiropoulos Photography/Getty Images/Flickr RF

Despite his father’s misgivings, Charles has pursued his own relationship with Greece, holidaying in Corfu as recently as last summer with Camilla. An affinity with Greek Orthodoxy – he has made many visits to the all-male monastic republic of Mount Athos – has earned him popular affection. He will meet the country’s spiritual leader, Archbishop Ieronymos, on Thursday.

Charles’s attraction to the Greek Orthodox church is such that he has auctioned his watercolour paintings to raise money for the renovation of ancient footpaths and his favourite monastery, Vatopedion, on Athos. The prince’s paternal grandmother, Aliki (Alice), was an Orthodox nun for most of her life.

On Tuesday, the prince also announced his Prince’s Trust charity would be expanding into the country with a view to helping “the young people of Greece achieve their full potential, whether through skills training or assisting them to set up their own enterprises”.

That it has fallen to a leftist government to host the couple has not been lost on many. But as the visit nears – with Betty Tsipras, the wife of the Greek prime minister, reportedly being fitted out by Athens’ leading haute couture designer – the excitement is palpable.

“This visit marks a new era in Anglo-Greek relations, its symbolic and very positive and I say that as a fanatical republican,” said Nikos Xydakis, the ruling Syriza party’s parliamentary spokesman. “Our ties go back to the creation of the modern Greek state, it is only right that after so many years this is happening.”

The niceties dictate that even Athens’ crown jewel, the fifth century BC Acropolis, will be avoided to avert the possibility of the Parthenon marbles dominating the visit. “It’s called tact,” quipped Xydakis, a former European affairs minister. “Diplomatic tact. Charles is a popular figure here and we want him to feel welcome.”

