ISLAMABAD (AP) -- China's premier began a two-day visit to Pakistan on Wednesday by praising the relationship between the two Asian powers in glowing terms.

Premier Li Keqiang said "the tree of China-Pakistan friendship" was planted decades ago, nurtured by successive leaders and "is now exuberant with abundant fruits."

Both sides are typically effusive in describing their alliance, underlying the mutual benefits to each side. Pakistani leaders have on previous visits described the relationship as "higher than mountains, deeper than oceans, stronger than steel and sweeter than honey."

China provides Pakistan with aid and foreign investment, while Islamabad offers Beijing important diplomatic backing in the face of Muslim-majority nations who might otherwise criticize China's handling of its minority Muslim Uighur population.

Pakistan has viewed China as an important counterweight to the United States, which provides valuable aid but often pressures Islamabad to do more to crack down on Islamic militants. Pakistan and China have also been close because of their mutual distrust of India, which borders both countries.

Li arrived in Islamabad on the heels of a visit to Pakistan's rival India, his first trip abroad since becoming premier in March. Li and Indian Prime Minister Manmohan Singh sought to downplay a recent border dispute and stressed the aim of forging deeper cooperation. They expressed hope they could increase trade from $61.5 billion last year to $100 billion by 2015.

Pakistan would also like to increase trade with China, although the numbers are much smaller. Trade between the two countries exceeded $12 billion for the first time in 2012, and they hope to reach $15 billion within three years, according to a statement by Pakistan's Foreign Ministry. The two countries are expected to sign agreements related to energy, technology and space during Li's visit. Pakistan suffers from severe energy shortages.

"Friendship with China is a cornerstone of our foreign policy," Pakistani President Asif Ali Zardari said in a speech Wednesday before a lunch hosted in Li's honor.

The lunch was attended by former Prime Minister Nawaz Sharif, whose Pakistan Muslim League-N party won a resounding victory in national elections on May 11 and is set to form the next government. Sharif's main focus is on turning around Pakistan's stuttering economy, and its relationship with China is an important factor in the country's growth.

China took over operational control of a strategic deep-water seaport on Pakistan's southwest coast earlier this year that could serve as a vital economic hub for Beijing and perhaps a key military outpost. Gwadar port on the Arabian Sea occupies a strategic location between South Asia, Central Asia and the Middle East. It lies near the Strait of Hormuz, gateway for about 20 percent of the world's oil.

China's interest is driven by concerns about energy security as it seeks to fuel its booming economy. It wants a place to anchor pipelines to secure oil and gas supplies from the Gulf. Beijing also believes that helping develop Pakistan will boost economic activity in its far western province of Xinjiang and dampen a simmering, low-intensity rebellion there.

China has expressed concerned that Uighur militants are living in northwest Pakistan alongside al-Qaida-linked extremists. Pakistan says it has killed or extradited several of those militants over the past few years, but acknowledges that some remain at-large in the area.