The works were expected to reduce rail traffic through Florence, a key hub on Italy’s high-speed train network, by about 50 percent through Thursday, July 30th, according to network operator RFI.

Some lines would provide a shuttle bus service between Florence’s Santa Maria Novella and Campo di Marte stations, increasing journey times by around 90 minutes, RFI said in a statement.

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Long-distance services on the Tyrrhenian line would be maintained with two trains per hour on the Rome-Milan/Turin route, it said, with expected delays of approximately two and a half hours.

Italian media warned of the country being “split in two” by the disruption at one of Italy's most important transport hubs linking the north and south of the country.

Updates on changed or cancelled trains are being made on this webpage. Real-time service updates can be accessed here.

The €17 million project to replace the 140-year-old Ponte al Pino overpass at Santa Maria Novella with a new steel-concrete structure began at 11pm on Sunday, July 26th, following an initial round of works to dismantle the bridge earlier in the month.

The work is scheduled to end by 11am on Thursday, though RFI warned service changes “may also occur before or after the scheduled work time.”

The operation “is one of the most complex engineering projects completed in recent years in the Tuscan capital”, the company said.

“The operations will take place in a highly urbanized area, making the construction site particularly complex from a technical and organisational standpoint.”

Tuscany's regional president Eugenio Giani earlier this month said the works were "a national emergency measure taken for the safety of commuters."