According to plan, the Hanoi People's Committee will build a passageway to connect Chuong Duong Do and Tran Nguyen Han streets. The passageway aims to ensure travelers' safety and reduce congestion when pedestrians cross the streets.

The local Ministry of Transport will inspect the location and set up the investment plan. The passageway is expected to be complete by the end of 2015.

Architect Dao Ngoc Nghiem said that the urban plan in 1992 already stated that Hanoi must build road junctions to connect the inner city with the suburbs. However, due to limited financial capacity, many junctions have not been built. To connect these areas, an overpass or underground passage should be built, and considering the current conditions, an underground passage is the most reasonable solution, Nghiem added.

However, he went on to say that to realise the plan authorities must not be too hasty, and take into account all possible factors, such as geological conditions and the rising sea level which could lead to serious flooding.

"What are we going to do if the flood level reaches 11.5m like the historic flood in 1971? I don't think we should carry out this plan now because of our limited financial and technological capacity to deal with such matters. Moreover, I don't think it's really necessary." he said.

Architect Tran Trong Hanh agreed and said authorities must be more cautious. "I haven't seen the plan so I can't comment much. But it's true that an underground project requires of scrutiny, especially when it comes to floods and climate change."