As part of his electoral platform, the former European Commission president is promising to restore and clean up the pilgrim ways of Italy — a pledge bound to win favour among the country’s millions of devout Roman Catholics.

He says that the project, to be financed by central and local government, would involve re-establishing footpaths and rights of way, tidying up the landscape and ensuring that pilgrims had access to inexpensive hostels.

Aides said that Signor Prodi hoped that British and French authorities would join him in reviving the Via Francigena (the Way of the Franks), which was founded in the 10th century by Sigeric, the Archbishop of Canterbury at the time.

The Via Francigena runs from Canterbury through Calais, Rheims, Besançon and Lausanne, crossing into Italy at the St Bernard Pass. It then reaches Rome via Aosta, Piacenza, Fidenza, Parma, Lucca, Siena and Viterbo. The 1,200 miles (1,931km) between Canterbury and Rome recently took one modern-day pilgrim 10 weeks, or 70 days, to walk.

Signor Prodi also hopes to revive the Via Carolingia, by which Charlemagne journeyed from Aachen to Rome to be crowned by Pope Leo III on Christmas Day 800, passing through Strasbourg, Basle, Como, Bergamo, Mantua, Ravenna, Ancona and Assisi. Signor Prodi also would like to restore the Italian leg of the traditional Christian route to the Holy Land, on which pilgrims embarked for Jaffa and Jerusalem at the port of Brindisi.

The project is inspired by the success of the 800km pilgrim path to the shrine of St James at Santiago de Compostela, in Galicia, northern Spain. The Santiago Way, first revived in the 1980s, attracted a record 180,000 pilgrims last year.

The tradition of pilgrimage to Rome began to decline with the Reformation in the 16th century and the disruption caused by wars. Corriere della Sera said that the Prodi project combined “the paths of power and the paths of the spirit”. Signor Prodi’s move is politically shrewd because it will appeal to environmentalists and Catholics. Signor Prodi is a devout Catholic but he has lost ground with the Italian Catholic hierachy by appearing to suggest that he would legalise same-sex unions if he returned to power.

Moves to revive the Via Francigena began a decade ago with the backing of the Council of Europe. The Via Francigena Association, in Fidenza, issued a vade mecum for travellers in 2000, a Holy Year. However, the route largely follows busy roads, and signposting and accommodation are inadequate.

Signor Prodi said that he hoped that pilgrims would discover the hidden beauties of Italy. He said: “A national identity is constructed not only by looking to the future but also by looking back to the past.” He disclosed his plan in a book of interviews with Italian politicians, Vincitori e Vinti (Winners and Losers), by the journalist Bruno Vespa.

Other left-wing leaders have disclosed hitherto unsuspected religious values. Piero Fassino, head of the former Communist Democrats of the Left, said that he had been educated by the Jesuits and still espoused Christian values.

Signor Prodi, who was Prime Minister from 1996 to 1998, appears likely to oust the centre-right coalition led by Silvio Berlusconi in April. Polls suggest that voters are disllusioned with Signor Berlusconi’s handling of the economy and with Italy’s role in Iraq.

Times Recommends

• Churchill 'bribed Franco's generals'
• The pitbull Palin is back on a leash
• US soldier fights to take Iraq dog home