KHARTOUM (Reuters) - U.S. senator and former presidential candidate John Kerry arrived in Sudan Wednesday for a three-day visit as the diplomatic detente between Washington and Khartoum shows further signs of a thaw.

Kerry, chairman of the U.S. Senate Foreign Relations Committee, will lead a congressional delegation to Sudan's Darfur region and hold talks with senior members of the Sudanese government.

"Now it is my opportunity representing the U.S. Congress and U.S. Senate to be here to engage on humanitarian issues and obviously issues pertaining to the conflict," Kerry told reporters after landing. "We're all very hopeful that we can make progress on these issues."

Kerry is not expected to meet with President Omar Hassan al-Bashir, who was last month indicted by the International Criminal Court on charges of war crimes.

Bashir Monday welcomed "positive signs" sent by U.S. President Barack Obama to the Islamic world.

Washington has had tense relations with the Islamist government of Bashir, who came to power in Africa's largest country in a 1989 coup.

The United States imposed economic sanctions on Sudan in 1997 and labeled it a "state sponsor of terrorism."

Ties were strained further by the conflict in Darfur, which both Obama and his predecessor George W. Bush have called genocide, a description Sudan's government rejects.

(Reporting by Alastair Sharp; Editing by Angus MacSwan)