China's President Xi Jinping arrived in Pakistan on April 20 where he is set to announce billions of dollars of major investments that could mark a dramatic expansion of China's influence in the country.
Xi is expected to reveal agreements that China will spend $46bn (£30.8bn, €42.8bn) on transport and energy infrastructure, including a vast network of roads, railway lines and pipelines that would reach 3,000km (1,865 miles) upon completion.
The network would reach from China's western Xinjiang province to the Pakistani coastal city of Gwadar, effectively providing China with unbroken access to the Indian Ocean.
The $46bn figure by far exceeds spending by the US in Pakistan and gives a strong signal of China's ambitions in the region.
The infrastructure projects are designed to establish an Economic Corridor between the old allies and the growing economic ties will be complimented by increased cooperation in matters of security.
The planned corridor will pass through the low-income and politically volatile province of Baluchistan, which has been home to an ongoing separatist insurgency for around a decade.
While Pakistan's government has not managed to quell the unrest, China hopes that the prospect of a major economic boost could push Islamabad to
In a statement to Pakistani media on Sunday, Xi said the two countries would work together on the issues.
"China and Pakistan need to align security concerns more closely to strengthen security cooperation," he said. "Our cooperation in the security and economic fields reinforce each other, and they must be advanced simultaneously."
The investment will be broken down between $34bn for energy projects and $12bn of concessional loans for infrastructure projects, according to Pakistani minister for planning and development Ahsan Iqbal.
Chinese banks and government will lend money to Chinese companies, who in turn will take on the Chinese - Pakistani projects as commercial ventures.
Around $28bn of deals are expected to be signed during the two-day summit, with the rest of the deals to be finalised later.
Xi is due to hold talks with his Pakistani counterpart, as well as the Prime Minister Nawaz Sharif, and is set to address the Pakistani parliament on Tuesday.