"I am extremely happy to visit Sudan at the invitation of president Omar al-Bashir," Hu said in a statement at the airport.

"Although the distance between China and Sudan is great, the friendship between the two people is deeply rooted."

'Bilateral relations'

A small crowd of Chinese residents and Chinese UN peacekeepers here waved Chinese and Sudanese flags as the two leaders reviewed a presidential guard.

Officials in Khartoum said Hu's visit was geared toward "bilateral relations and other important issues of common interest," without specifying if these would be commercial matters or would include human rights issues.

Khartoum expects its staunchest diplomatic ally to stick to boosting commercial ties, particularly for Sudan's oil.

But Beijing has raised expectations that Hu may bring some pressure on Khartoum to show flexibility in ending Darfur's bloodshed.

Chinese officials ahead of Hu's visit urged Sudan to cooperate in finding a solution in Darfur in rare public pronouncements under China's traditional refusal to interfere in what it considers other countries' internal affairs.

"This visit is going to be a great boost for the distinguished Sudanese-Chinese relations in various fields," al-Bashir said on Thursday.

China, which is the biggest foreign investor in Sudan and buys two-thirds of the country's oil exports, has used its veto-wielding status at the UN security council to prevent harsh measures against Sudan over the Darfur conflict.

Sudan has refused demands it allow UN peacekeepers into the region, calling "neocolonial" a UN security council plan to replace an overwhelmed African Union force in the region with some 22,000 UN peacekeepers.