Officials and experts say regional coordinated development is the only effective way for Beijing to solve its problems.

Closer cooperation among the three is under way. For example, they have a mechanism for joint prevention and control of air pollution. Construction of a new airport in Beijing will begin this year on the capital's outskirts neighboring Langfang.

However, the regional integration faces challenges in aspects like unbalanced industrial distribution and environmental pressures.

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Beijing, Hebei and Tianjin reported the heaviest air pollution last year in the country, according to the Ministry of Environmental Protection.

Hebei boasts several of the most polluted cities such as its capital Shijiazhuang and Xingtai due to heavy industries like iron and steel. It plans to cut iron production capacity by 28 million tons and steel production capacity by 40 million tons by 2017.

"We must have a clear idea of the environment capacities of the three places so that we know what kind of industries and how much Hebei can take from Beijing or Tianjin," said Wu Yiqing, vice president of Hebei University of Economics and Business.

If the environment does not improve by 2017, steel capacities in Hebei may be further cut, said Wu.

The region has big food demand but Hebei's agriculture is at an initial phase of modernization, said Zhou.

"To push forward coordinated development is undoubtedly the right direction, but the process will not be smooth given the risks and challenges," said Wu.

Short, medium and long-term timetables should be formulated on the basis of consensus and coordination be strengthened to handle new problems in the process, he added.

To remove administrative barriers and push regional coordinated development will be one of the key reform tasks for Beijing this year, said Wang Anshun, mayor of the city.

Unified top-level design should be made for the integration of infrastructure, industries and market in the region, said Wang during the China Development Forum held on March 23-24 in Beijing.