The Manx government has announced plans to buy the Isle of Man Steam Packet Company (IoMSPC) for £124m.
If approved by Tynwald later this month, the deal would see government commit to purchase 100% of MIOM Ltd, the IoMSPC's parent company.
Chief Minister Howard Quayle said: "Acquiring the national asset is a once-in-a-generation opportunity."
The IoMSPC provides freight, passenger and vehicle services between Douglas and five ports in the UK and Ireland.
The government has been considering its options since rejecting the company's revised offer of a new strategic sea services agreement in July 2017.
It had proposed to invest £170m in services - including spending £65m on two "state-of-the-art" ships - had its contract been extended.
Treasury Minister Alfred Cannan said: "The deal would immediately bring ferry operations into public ownership but government would not take over the day-to-day running of services."
He said government could "put in place a new agreement within 12 months" if the deal goes ahead.
Mr Cannan said: "We believe we are paying a fair price to secure a profitable, cash generative national asset and gain strategic control of our sea services."
Steam Packet CEO Mark Woodward said a deal would "consolidate an excellent relationship" and create a "strong, long-term platform to deliver continued investment and sea services that meet the needs of the island".
A government spokesman said its finances would be restructured to minimise the outlay from reserves - no further details have been revealed.
Mr Quayle said the proposed deal follows extensive assessment of potential operating models, port facilities, and vessels.