Cairns-based shipping and freight company Sea Swift has announced a game-changing purchase of its competitor's major North Australian assets after winning approval from the competition watchdog.

Sea Swift's staff numbers will swell to around 400 people after the Australian Competition and Consumer Commission (ACCC) finally approved Sea Swift's proposed buy out of Toll Marine Logistic's general freight assets in North Queensland and the Northern Territory.

Under the multi-million dollar deal, Sea Swift will acquire Toll’s marine Cairns and Darwin-based assets and take over its services and supply activities in the region.

The proposed deal was first put to the Australian Securities Exchange in November 2014. But the move was initially rejected by the ACCC.

After a lengthy appeals process by the two companies at the Australian Competition Tribunal, the buy-out has now been approved.

Sea Swift CEO Fred White told TropicNow the decision paves the way for a major expansion of the Cairns-based shipping company.

Mr White said the company's headquarters would remain in Cairns, with a range of support services and logistical functions to be managed from its Portsmith base.

"Sea Swift and Toll will now be working collaboratively with customers and suppliers to ensure essential services to remote northern Australia transition smoothly to Sea Swift and remain unaffected by the change," Mr White said.

"As far as we are concerned, we pride ourselves on our customer service levels and this will not change.

“For existing staff this will provide the opportunities that come with being part of a larger growing organisation.

“Sea Swift would like to take this opportunity to thank their customers, suppliers and staff for their continued support, and trust that this transaction will further enhance service levels across the region."