Chinese President Xi Jinping on Monday urged world leaders to reject protectionism at a summit on his Silk Road plan, even as some countries expressed concern over Beijing's trade and geopolitical ambitions.

Xi has used the summit to showcase his signature One Belt, One Road initiative, a multi-year plan to build a web of infrastructure and transport links connecting Asia, Europe, Africa and other regions.

Read: New Silk Road' and China's hegemonic ambitions

"We need to seek win-win results through greater openness and cooperation, avoid fragmentation, refrain from setting inhibitive thresholds for cooperation or pursuing exclusive arrangements and reject protectionism," Xi said on the second day of the summit in Beijing.

Read: China's new Silk Road - perception and reality

Xi has used the summit to portray China as an open economy in contrast to rising protectionism at a time US President Donald Trump pursues an "America First" policy.

The Silk Road initiative, first proposed by Xi in 2013, is also viewed as a counterweight to the Trans-Pacific Partnership (TPP), a regional trade pact that excludes China. Negotiated by the Obama administration, TPP is effectively on ice after Trump withdrew US support.

On Sunday, China pledged $124 billion (113 billion euros) to fund infrastructure projects. The China Development Bank had also designated $890 billion for nearly 900 projects.

Russian President Vladimir Putin, Turkish leader Recep Tayyip Erdogan and British Foreign Minister Boris Johnson among others supported the Chinese vision.

Despite China's claims to support openness, some business and western countries have expressed doubt over issues like transparency, fair competition, labor standards and the environment. They also accuse Beijing of maintaining protectionist policies that favor Chinese business and geopolitical interests.

German Economy Minister Brigitte Zypries said Sunday the EU would not join the Chinese initiative unless issues like transparency, fairness in tenders, environmental protection and conformity with international trade standards were met.

Read: Germany wants more guarantees from China over Silk Road trade plan

Economists have also warned of saddling developing countries with debt by building infrastructure projects that make little economic sense.

"Unprofitable investments are not good for anybody," said Andras Vertes, chairman of GKI Economic Research.

Xi has advocated for aligning projects with the development goals of institutions such as the Asia-Pacific Economic Cooperation (APEC), ASEAN, African Union and the European Union.

Watch video 00:37 China hosts Silk Road summit

cw/rt (AFP, Reuters)