President Tran Duc Luong has sent a letter to national workers and foreign experts on the Hai Van tunnel project, saying he was overjoyed to hear they had met up last Tuesday to complete the 6.7km passage.

A section of Hai Van tunnel.

The President praised the workers and experts from Vietnam, Japan and the Republic of Korea for being efficient, ensuring quality and safety, and coming in on budget.

The Director of the project, Nguyen Thanh Tra, said a ceremony will be held on November 7 to celebrate the technical completion of the tunnel, which is the largest of its kind in Vietnam.

But he said more work needed to be done before the toll-way tunnel officially opens to traffic in the middle of next year.

Once it is finished, the tunnel will be one of the 30 largest tunnels in the world, measuring 11.9m across, with a 4.7m-wide emergency tunnel. It should be able to accommodate vehicles up to 30 tonnes travelling at 80km/h.

Work on the US$251mil tunnel began in August 2000, with 85% of its funding drawn from official development assistance loans from the Japan Bank for International Co-operation.

A joint venture between Japanese company Hazama and the Civil Engineering Construction Corporation dug from the northern side of the mountain to meet up with a consortium formed by Song Da Construction Corporation and the Korean firm Dong Ah coming from the southern side.