Near-record low water levels are affecting river cruising on the Danube River, according to a report by Reuters.

The news agency said that the decrease is impacting cruise operations and wider tourism activities in Hungary.

Reuters said that vessels have been stranded north of Budapest, as the Danube’s water level in the city fell to within eight centimeters of past low-level records on Thursday morning.

River cruise operator Avalon Waterways was quoted as saying that it had been forced to cancel what it described as a small number of upcoming departures earlier this week.

The company noted that the changes to its schedule were related to low water levels on the Danube and Rhine rivers.

Other activities, including sightseeing trips and day cruises, are also affected by the situation, Reuters added.

Viking is informing guests of itinerary changes in a series of individual emails, according to reports from guests on social media.

Cruise Industry News found reports of passengers being transferred between certain destinations by bus for itineraries on the Danube and Rhine rivers.

AmaWaterways issued a travel alert on its website, noting that unusually low water levels are affecting sections of the two rivers.

“As river conditions continue to evolve, modifications may include changes to ports, embarkation or disembarkation locations, motorcoach transfers, ship scheduling or other itinerary elements,” the company explained.

“Please know that every adjustment is made with the comfort and safety of guests as our highest priority,” AmaWaterways added, noting that guests on affected sailings are being contacted individually via email.

Other companies, including Riviera Travel River Cruises, are reportedly also affected by the low levels.

“During the summer months, water levels can fluctuate on Europe’s rivers which may result in low water conditions in specific destinations,” the company stated on its travel advice page.

“As ever, we monitor this very closely and we will contact you immediately if there is likely to be any impact to your upcoming cruise,” Riviera continued.

While notices are issued with as much notice as possible, the situation can evolve rapidly, the company added.

As a result, Riviera said that “it is impossible” to predict if a cruise will be affected more than a few days in advance.