China has offered more than $3 billion in loans and aid to neighbors Cambodia, Vietnam, Myanmar, Thailand and Laos to improve infrastructure and production, and to fight poverty, state media reported on Saturday.

Chinese Premier Li Keqiang said the offer included $1 billion for infrastructure, $490 million for poverty alleviation and $1.6 billion in special loans for China's production capacity export, Xinhua news agency said.

During a speech to the fifth summit of the Greater Mekong Subregion (GMS) Economic Cooperation in Bangkok, Li also pledged $16.4 million to dredge waterways along the Mekong River to prevent natural disasters.

"These are important parts of our efforts to upgrade China- ASEAN cooperation ... we are ready to work with the five countries to build a new framework to deepen cooperation and bring the GMS comprehensive partnership to a new level," Li said.

He said China planned to export high-level production capacity in electricity, telecommunications, steel and cement to its neighbors on regional transportation routes, Xinhua reported.

Li is in Thailand attending a two-day summit of leaders of Mekong River region countries, the biggest international gathering in Thailand since its military seized power.

Cambodia's PM Hun Sen, Thailand's PM Prayuth, China's Premier Li and Myanmar's President Thein Sein join hands in Bangkok Thomson Reuters China will finance projects by offering special loans, currency swaps in cross-border transactions and by allowing a role for private enterprises, Li said.

On Friday, China said it would build an 867-km rail network in Thailand and buy two million tonnes of its rice.

Li offered $20 billion in loans for Southeast Asia during a regional meeting in Myanmar last month. It is not clear if the money announced in Bangkok was part of that figure or represented new funds.

More than $120 billion has been promised by China since May to Africa, Southeast Asia and Central Asia as Beijing tries to present a softer, more cooperative side to the world following months of tension over territorial issues and other problems.

"We'll create new levels of industrial cooperation. China has become the most important trade partner in the sub region and our investment will increase. . . We have every reason to draw on each others' strengths," Li added.

China has set nerves of edge in Southeast Asia with its claims to the South China Sea, which have rankled Vietnam and the Philippines in particular.

Southeast Asia has also emerged as a new area of strategic competition between China and the United States, and China has been keen to present a softer side to the region, partly though offering massive new funding for infrastructure projects.

(Reporting by Engen Tham and Martin Petty; Additional reporting by Ben Blanchard; Editing by Jeremy Laurence)