Chinese experts on international relations said on Sunday that President Xi Jinping's first foreign trip as head of state has strengthened relations with China's neighbors, Africa and emerging economies.

Xi returned to Beijing on Sunday after state visits to Russia and three African countries between March 22 and 30.

Xi's tour further solidifies the China-Russia comprehensive strategic partnership of coordination and Sino-African cooperation in economic and social fields, and the visits promote institutional collaboration among emerging economies, said Prof. Zhu Feng of the School of International Studies with the Peking University.

During the first leg of Xi's trip in Russia, China's biggest neighbor, the two sides signed cooperation agreements, dubbed the "contracts of the century" because they are enormous in value and cover a long period of time, Foreign Minister Wang Yi told media on Sunday.

Wang said that choosing Russia as the first stop of Xi's tour has shown the high level and distinctiveness of China-Russia relations.

Xi's Russia visit has "strategic significance," according to Gong Li, deputy director of the International Institute of Strategic Studies with the Party School of the Communist Party of China Central Committee.

During the African part of the trip, Xi visited Tanzania, South Africa and the Republic of the Congo.

"Africa is the main dependent strength of China's diplomacy," Gong said, adding Xi's African trip enhances friendship with emerging African countries and strengthens the foothold of China's diplomacy.

Zhu said an important signal sent from Xi's speech in Africa was that Sino-African cooperation has turned to an all-round one including more social and cultural exchanges, from the old partnership driven by the economy and natural resources.

Sino-African relations have become more "practical," said Dong Manyuan, deputy director of the China Institute of International Studies, adding that the bilateral relations always "provide timely help."

In Africa, Xi said China will train various personnel for African countries, enhance technological transfers to Africa, share more experience with the continent and attach more importance to Sino-African cultural exchanges.

"More aid projects provided by China to Africa are about livelihood improvement," Dong said, adding China is seeking to help Africa create sustainability by improving local employment and people's livelihoods.

Xi made clear through his visit that the Sino-African cooperation suits both Africa's short- and long-term interests, noted Dong.

"Sino-African cooperation is distinct from the aid provided by some Western nations," he said, adding China respects the development roads and political systems that are suitable and chosen by African countries on their own, whereas "the aid offered by the West often comes with political conditions."

Xi's visit was the best refutation to "Chinese neocolonialism in Africa," an allegation made by many in the West against China, Dong said.

The Sino-African cooperation is gradually shaking off various "ill-disposed" allegations, such as the "China Threat Theory" and "neocolonialism," and is heading for a win-win development with mutual benefit, the expert said.

In a speech in Tanzania, Xi recalled older generations of leaders such as late Chairman Mao Zedong and late Premier Zhou Enlai who established sincere friendship with Africa. Xi also said China and Africa are interdependent.

Xi reminds many Chinese enterprises and businessmen in African to "focus more on long-term interests and building up affection," said Prof. Zhu Feng.

The Chinese leader also attended the fifth BRICS summit held in Durban, South Africa, on Tuesday and Wednesday.

According to Wang Yi, the summit has promoted unity among major emerging economies and injected fresh impetus into the development of a cooperation mechanism.

Gong Li said cooperation among the BRICS nations is "going deep."

The leaders agreed to set up a BRICS development bank, a Contingent Reserve Arrangement, a business council and a think tank council.

The close cooperation among BRICS nations expands their fields of discussions from the economy to politics, Gong said, adding the fruits are related to China's rise in comprehensive power and the world's trust in China's new leaders.