By Bill Hayton
BBC News, Hanoi
The Vietnamese authorities have approved plans to build a $33bn (£15bn) rail link between the capital, Hanoi, to Ho Chi Minh City in the south.
If completed, it could cut the journey time between the two cities from nearly two days to less than 10 hours.
The government has set an ambitious target - it wants the link built in just six years.
The existing 1,600km (1,000 mile) trip is one of the great railway journeys of the world.
Crossing swamps and forest, in places hugging the shore line, some of the views are spectacular and there is plenty of time to enjoy them.
The fastest train takes 29 hours and the slowest 40.
Built by French colonialists and repeatedly blown up during the Vietnam war, the single track line needs major improvements.
The state railway company's original plan was to do it over nine years, but the prime minister has ordered them to do it in six.
The new railway will be one of the country's biggest ever investment projects.
Vietnam does not have that kind of money, but the Japanese and South Korean governments are offering assistance. But both countries want their companies to do the work.
With such key details as this still to be resolved, it will be an impressive achievement if the line is finished by the prime minister's deadline.