Pakistan's Prime Minister Nawaz Sharif on Friday told his Chinese counterpart Li Keqiang their countries' relationship was "sweeter than honey", during a visit to Beijing with economic ties at the top of the agenda.

Pakistan and China are close diplomatic and military allies and Sharif, who is on his first foreign trip since his May election, is looking to secure infrastructure projects to tackle a chronic energy crisis and economic malaise in his country.

At the Great Hall of the People in the Chinese capital, Sharif said his welcome "reminds me of the saying, our friendship is higher than the Himalayas and deeper than the deepest sea in the world, and sweeter than honey".

Li told him: "I greatly appreciate your great warmth and deep affection for the people of China."

The Chinese premier was the first foreign leader to visit Pakistan after Sharif's victory at the polls.

Beijing has been involved with the upgrade of the Karakoram Highway as part of a proposed economic corridor between the two countries.

Earlier this year China took control of Pakistan's Gwadar port, giving it access to the Arabian Sea and Strait of Hormuz, a gateway for a third of the world's traded oil.

A series of agreements were signed by ministers of the two countries as Li and Sharif held talks.

Among these was a "long term plan" over the economic corridor, and agreements on technology, polio prevention and solar housing.

An agreement was also signed for cooperation between Sharif's Pakistan Muslim League-N (PML-N) and the Communist Party of China (CPC).

The two countries also agreed a $44 million project to erect a fibre optic cable from the China-Pakistan border to Rawalpindi, which aims to give Pakistan more connectivity to international networks.

China-Pakistan trade last year reached $12 billion and is targeted to rise to $15 billion in the next two to three years.

On Thursday Sharif held talks with Chinese President Xi Jinping, amid concerns in his country over weak growth, inflation and power cuts of up to 20 hours a day.

Xi, who referred to Sharif as an old friend and a good brother, said strengthening strategic cooperation with Islamabad was a priority for China's diplomacy, the state-run broadcaster China Central Television reported.

Sharif said his country welcomed Chinese investment and would work to create a friendly environment for it.

The threat of terrorism is also expected to figure during Sharif's discussions.