Dowsett announced his attempt on November 10, with the 32-year-old seeking to set a record for the second time.

The attempt was initially scheduled to take place on December 12 at the National Cycling Centre Velodrome in Manchester.

Dowsett suffers from haemophilia A and was planning to raise money for charity.

"I am really disappointed the attempt can’t go ahead as planned but my health is first and foremost the priority," Dowsett said, following the postponement.

"I’d like to thank everyone, the event organisers, event sponsors, my team, the UCI and above all the public for their support and very much look forward to attacking the record in 2021 with the same intent.

"We’re looking to announce a 2021 date as soon as possible."

The record for the longest distance covered in one hour is currently held by Belgium’s Victor Campenaerts.

Campenaerts set the mark of 55.089 kilometres in Mexico in April last year.

The record was achieved at altitude at the Velodromo Bicentenario in Aguascalientes.

Campenaerts effort surpassed the 54.526km covered by Britain’s Sir Bradley Wiggins back in 2015.

Sir Bradley had broken Dowsett’s record, which he set at 52.927km 36 days earlier.

The hour record has attracted interest from riders since regulations were updated in 2014 to permit the use of the latest pursuit bikes.

Dowsett had been coming into the hour record attempt on the back of earning a stage victory at the Giro d’Italia in October.

It was the second Giro d’Italia stage victory of his career, following a time trial success back in 2013.

Dowsett signed a two-year contract extension with Israel Start-Up Nation last month.

He will be joined on the team next year by fellow Briton Chris Froome, who will be expected to lead their challenge at Grand Tours.