Egypt's President Abdel Fattah el-Sisi has formally opened the new Suez Canal expansion, allowing two-way traffic for the first time via a 75 km parallel channel that will reduce transit times by up to seven hours.

CMA CGM's 11,400 teu CMA CGM Titan, and Mediterranean Shipping Co 13,000 teu MSC Capella, headed the processions in each direction.

In a speech at the official opening ceremony, President Sisi said the work had been carried out in Egypt "in extreme circumstances, in hard times".

It had been critical that the canal was completed on schedule, he added.

"The new canal is not only an engineering feat, but it was the first step in a further thousand steps to develop Egypt," said President Sisi. "We promised the canal as a gift to the world and have fulfilled this in record time, providing an artery for additional trade."

But questions remain over the $4bn cost of the project and the Suez Canal Authority's projections for revenues from the canal. Last year the SCA earned $5bn from transit fees but it expects this to rise to $13bn by 2023.

With world trade forecast to grow at only around 4% during the same period, it is hard to see where the canal's more than 150% revenue growth will come from, but the SCA said the figure was in line with its forecasts and financial modelling.

Around 15% of all world trade goes through the canal, and the SCA said that while average growth may be low, it would benefit from the parts of the market that were growing faster, and that the expansion project would bring more traffic through the canal.

Speaking to Lloyd's List ahead of the opening ceremony, Maersk Group representative and Maersk Drilling chief executive Claus Hemmingsen said the wider world would benefit from the shorter transit times, better schedule reliability for transits, and from an increased number of large vessels being able to pass through the canal.

"The concerns we had that restrictions would have been imposed have been eliminated," Mr Hemmingsen said. "The new canal accommodates the growth that has taken place over the past 10 years."

Maersk and the canal have a symbiotic relationship. The line is the canal's biggest customer, spending $750m a year on more than 1,400 transits.

The Suez Canal accounts for roughly 7.5% of world sea trade, with containerships representing over 50% of the canal's tonnage.

Maersk Line ships account for around 20% of the container transits, and virtually all Maersk's Asia-Europe cargo goes through the canal.

Consequently, the Danish company has worked alongside the SCA in developing the canal.

Mr Hemmingsen participated in the official opening, along with  Maersk Line chief operating officer Søren Toft.

"The Suez Canal is a key corridor on the east-west trade. Maersk has used the corridor for more than 90 years and we welcome the easier transit and reduced transit times that the new expansion will bring,¡± said Mr Hemmingsen shortly before the official opening.

He also played down fears that the canal could increase tariffs excessively.

"We don't expect the canal to leverage the expansion to hike tariffs," he said.

The new channel will enable transit times to be cut from 18 hours to 11 hours, so reducing both fuel consumption and emissions.

Moreover, the canal will have a daily capacity of 97 transits, up from the current 47 ships per day.

The Suez Canal can already handle the world's largest ships such as the new generation of 19,000 teu containerships, whereas the expanded Panama Canal will only be able to take ships of up to14,000 teu even after the new locks are completed next year. But the two larger waterways will give both ship operators and their customers more choice, especially in the Asia-US container trades.

Traditionally, most containerised cargo from Asia has been shipped across the Pacific, with the bulk then offloaded on the North American west coast and moved by rail to destinations as far as the Ohio valley.

In the past, only a relatively small share has moved via the Panama Canal to the US Gulf and east coasts, because of the size limitation of ships that are currently restricted to about 5,000 teu. In contrast, vessels of up to 14,000 teu have entered the transpacific trade over the past two or three years, and these will soon be able to transit the Panama Canal once the enlargement project is completed.

Disruption on the west coast coast over the winter forced lines to look for alternative routes, with the Suez Canal gaining market share at the expense of the US west coast and all-water services through the Panama Canal, especially for cargo from Southeast Asia. US Atlantic coast ports are working hard to improve their facilities.

The expansion of the Suez Canal, giving it much greater capacity, will add to the competitive pressures on the transpacific trades and the expanded Panama Canal.