Xi told Prime Minister Alexis Tsipras that Greece was an important part in China's new Silk Road strategy.

"At present, China and Greece's traditional friendship and cooperation continues to glow with new dynamism," China's Foreign Ministry cited Xi as saying.

Cooperation in infrastructure, energy and telecommunications should be "deep and solid", Xi added, without giving details.

Tsipras is in Beijing to attend a summit to promote Xi's vision of expanding links between Asia, Africa and Europe underpinned by billions of dollars in infrastructure investment called the Belt and Road initiative.

Greek infrastructure development group Copelouzos has signed a deal with China's Shenhua Group to cooperate in green energy projects and the upgrade of power plants in Greece and other countries, the Greek company said on Friday.

The deal will involve total investment of 3 billion euros ($3.28 billion), Copelouzos said in a statement, without providing further details.

China has been investing heavily in Greece in recent years.

Its biggest shipping company, COSCO Shipping, bought a majority stake in Piraeus Port Authority last year under a plan to turn Greece into a transhipment hub for rapidly growing trade between Asia and Eastern Europe.

Xi said China and Greece should focus their efforts on turning the Piraeus port into an important international transhipment hub and key part of the new Silk Road, the Chinese ministry said.

China State Grid also agreed last year to buy a 24 percent stake in power grid operator ADMIE for 320 million euros.

Greek government borrowing costs hit their lowest level in more than five years this week as the troubled euro zone state looks close to clinching a deal with its creditors to release new loans to it.

After six months of tense talks, Athens and its international lenders - the European Union and International Monetary Fund - reached a provisional deal last week on the reforms needed to release new loans.