MAERSK Line has raised hopes that its proposed P3 containership-sharing alliance with the world's number two and three, MSC and CMA CGM, will start operating mid year after gaining US regulatory approval.

To cut costs, the three European ocean lines have agreed to pool 250 ships to operate three trade routes: Asia-Europe, transpacific and transatlantic.

The approval from the US Federal Maritime Commission (FMC) will apply only to routes to and from US ports. The alliance still needs approval from Chinese and European regulators before it can become fully effective.

Maersk said it expected to receive Chinese and EU approval before the middle of this year. "We expect that the P3 can be started mid-2014," it said in a Reuters report.

"North America and the US in particular is a key shipping market. Therefore, the decision by the FMC is a very important step towards overall approval of P3," said a Maersk spokesman.

He estimates the alliance will operate with ships that are on average 2,000-3,000 TEU bigger than its closest rivals.