As many as 120 jobs could be affected in a management shake up at P&O Ferries.
The proposal would lead to a loss of 60 jobs in the UK with another 60 being “restructured” into new or similar roles.
The ferry company confirmed that staff consultations had begun, with the GMB union and government informed of its intentions.
The planned restructuring comes just over a year since the company, owned by Dubai-based DP World, drew criticism from government and unions for abruptly dismissing 800 seafarers without notice.
A P&O Ferries spokesperson said: “We are consulting with our colleagues and trade unions about proposed changes to our management structure.
“Our proposals aim to put us on a competitive, sustainable footing, and deliver for our customers by offering the best-in-class service on the vital UK tourist and trade routes that we serve.
“These proposals do not affect our operational colleagues below leadership level in any of our UK, Ireland or European ports or any colleagues aboard our vessels.”
They added: “We are focused on investing heavily to meet the long-term needs of our customers who want value for money, greener journeys and flexibility. We have already improved our service, boosted our competitiveness, and are generating growth while significantly reducing our carbon emissions.
“On the key Dover-Calais route alone we save more than 85,000 tonnes of carbon emissions annually, and our new hybrid ships coming into service this year will further cut our carbon footprint.
“Our level of investment in new technology and capacity is unprecedented in the UK passenger and freight maritime industry, and demonstrates our long-term commitment to supporting the growth of the UK economy.”
The company has said a new hybrid vessel will cut fuel used on Dover-Calais crossings by 40%.
The P&O Pioneer is due to enter service on the English Channel short sea route in May.