ISLAMABAD: The Peoples Republic of China has reaffirmed its commitment for the multi-billion dollar project of China-Pakistan Economic Corridor (CPEC), the fate of which was sealed during Chinese President Xi Jinping's momentous visit to Pakistan earlier this month.

This was stated when China's Ambassador to Pakistan Sun Weidong called on Prime Minister Nawaz Sharif at the prime minister house on Thursday where he presented a letter from the Chinese president to the premier, a statement issued from the PM House said.

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In the letter, Chinese President Xi Jinping upheld Beijing's commitment for the implementation and success of the economic corridor, the culmination of which is expected to further reinforce the friendship between the "iron brothers".

Jinping also conveyed his thanks to the prime minister for the hospitality extended to him by Islamabad and the excellent arrangements made to ensure a successful visit.

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During Xi's much talked-about visit, Pakistani and Chinese officials signed a series of more than 50 accords to inaugurate the China-Pakistan Economic Corridor, which will create a network of roads, railways and pipelines linking China's restive west to the Arabian Sea through Pakistan.

Also read: Analysis: China-Pakistan corridor or labyrinth?

The project is part of Beijing's “Belt and Road” plan to expand its trade and transport footprint across Central and South Asia. It will give China easier access to Middle Eastern oil via the deepwater port of Gwadar.

The project generated controversy with political leaders particularly of smaller provinces alleging the project has been altered to benefit Punjab.

The route apparently under its original plan ran from Gwadar to Quetta, then up to Zhob before veering east towards Dera Ismail Khan.

Read: Cabinet okays Pak-China economic corridor

The government was criticised for having changed this route to go straight east from Gwadar towards Khuzdar, then slightly northeast to cross the River Indus near Ratodero and connect with the road network in Sindh.

Read Dawn editorial: Corridor furore

The government strenuously denied that any route changes were made, arguing that two routes are being pursued, and on the request of the Chinese, the second route is being built first simply because it is cheaper to do so.

Know more: Sound bytes: 'Economic corridor will have multiple routes’

The central route will link Gwadar, Khuzdar and other areas on way to Dera Ghazi Khan, Dera Ismail Khan and Peshawar, while the eastern route will connect Gwadar to Ratodero, Sukkur and Karachi and upward to cities in Punjab and from there to Khyber Pakhtunkhwa and then Khunjerab Pass.

Then there have been security concerns over much of the plan, which relies on developing Gwadar — control of which was passed to a Chinese company in 2013.

Take a look: Security fears for China-Pakistan corridor as Xi ends visit

The port lies near the mouth of the Gulf of Oman, east of the Strait of Hormuz through which much of the Middle East's crude production passes.

Read: Economists call for more transparency on corridor projects

But linking Gwadar to the rest of Pakistan and on to the western Chinese city of Kashgar, 3,000 kilometres (1,860 miles) away, would involve major infrastructure work in Balochistan. This is one of Pakistan's most unstable provinces and has been dogged for over a decade by a bloody separatist insurgency.

Ethnic Baloch rebels, who oppose Gwadar's development while the province is not independent, have in the past blown up numerous gas pipelines and trains and attacked Chinese engineers.

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