Leaders of Pacific Rim economies reached a consensus Sunday to commit themselves to freer trade with an aim of furthering regional economic integration, amid cautions that differences would impede any realization of a common vision.

Wrapping up the two-day, 21-member Asia-Pacific Economic Cooperation (APEC) summit in Yokohama, Japan, leaders also pledged to tackle trade barriers and protectionism for greater economic liberalization and balanced economic growth.

The leaders pledged to "take concrete steps" toward realization of a Free Trade Area of the Asia-Pacific region (FTAAP), which is a "major instrument to furthering APEC's regional economic integration agenda," said a final declaration called "The Yokohama Vision - Bogor and Beyond."

A timetable on establishing such a grand zone was not given.

The zone would cover more than half the world's economic output and connect major economies, including the United States, China and Japan, with some of the fastest-growing emerging economies, such as Indonesia and Thailand.

The declaration adds that integration will be based on the Trans-Pacific Partnership, or TPP - a US-backed, free-trade agreement - and on the ASEAN+3 grouping, which features ASEAN members plus Japan, China and South Korea, as well as ASEAN+6, which features the ASEAN+3 in addition to India, Australia and New Zealand.

The blueprint is the latest effort by APEC leaders to achieve free-trade and economic liberalization. Leaders attending the 1994 APEC summit in the Indonesian city of Bogor agreed on goals to remove trade and investment hurdles for the group's industrialized nations by this year, and for developing members by 2020.

Addressing the 18th APEC Economic Leaders' Meeting, Chinese President Hu Jintao said, "This year marked the deadline for the industrialized APEC economies to achieve the Bogor Goals of free and open trade and investment. APEC should continue to uphold the spirit of the Bogor Goals."

However, APEC leaders acknowledged that "it is a fair statement to say that the economies have some way to go to achieve free and open trade in the region."

Shen Shishun, at the China Institute of International Studies, told the Global Times that at least a decades-long effort must be made until the realization of the blueprint.

"Leaders have displayed their strong political wills, but the realization of the blueprint is an arduous task, for APEC members share many differences in their economies, cultures and religions," Shen said.

"The signing of the FTA among China, Japan and South Korea, the three major economies in the region, will foster the achievement of setting up a region-wide, free-trade zone," he added.

The possibilities of forging a trilateral free-trade agreement among China, Japan and South Korea have been researched since 2009 during meetings between economic and trade ministers of the three countries, but no concrete agreements are on the horizon.

Chinese Ministry of Commerce officials said in June that negotiations between China and South Korea for a long-awaited FTA would kick off at year's end or next year.

According to the latest data released by the Japanese government, APEC accounts for 53 percent of the world's gross domestic product and 44.4 percent of global trade by value. The member economies represent 40 percent of the world's population.