China's shipping giant COSCO is partnering with Malaysia's main rail operator Keretapi Tanah Melayu Berhad (KTMB) to carry freight cargoes on its railways to improve efficiency and free up the country's roads.

The rail-sea service, which started on Wednesday, will cover major regions in West Malaysia and connect 579 ports in approximately 140 countries and regions worldwide, COSCO Shipping Lines (Malaysia) said in a statement.

"The wide global network of these two companies will provide customers with transportation services that are global in coverage, stable, convenient, fast and environmentally friendly creating a one-stop service experience," it said.

"As a one-stop service model that integrates different transport modes, optimizes transport routes and balances timeliness and costs, the rail-sea transportation service will provide more efficient and convenient new experiences for international trade and transportation logistics for more enterprises," it added.

The start of the service was marked by a ceremony with Malaysian Transport Minister Anthony Loke Siew Fook, Minister of the Chinese Embassy in Malaysia Tang Rui, Vice President of COSCO Shipping Southeast Asia Zhou Ganfei and KTMB group CEO Mohd Rani Hisham Samsudin being among those in attendance.

Loke said the rail-sea service would greatly reduce the amount of freight being sent via Malaysia's roads, reducing congestion and pollution at the same time while improving delivery times.

"When moving or repositioning container boxes between our ports, instead of conventional shipping or hauling by trucks, transport by rail offers significant benefits. It is safer, more economical, and it is more sustainable with lower emission," he said.

"The new partnership leverages the strengths of both companies to provide greater solutions for customers in the region. COSCO's expertise in shipping and logistics combined with KTMB's extensive network and experience in Malaysia's transportation sector create a powerful synergy that benefits all," he added.

For his part, Tang said the rail-sea service builds on the impressive achievements made in port and logistics cooperation, with Kuantan Industrial Park successfully linked to the Port of Kuantan and the East Coast Railway Link (ECRL), which is under construction, smoothly connecting the whole Malaysia.

"Cooperation between China and Malaysia is flourishing in all fields which has brought tangible benefits to peoples of both countries," he added.