FACTBOX: Ups and downs of Sudan's ties with Washington

(Reuters) - U.S. President Barack Obama unveiled a new strategy toward Sudan on Monday, offering incentives if the Khartoum government worked toward peace, but said it faced tougher steps if it failed to act.

Obama called for a "definitive end" to the conflict in Darfur, and implementation of a troubled peace deal that ended over two decades of a separate civil war with the south.

Here are some facts about the conflict in Sudan and Khartoum's ties with Washington.

* U.S. ties with Sudan's Islamist central government in Khartoum have been tense for decades over a north-south civil war, Khartoum's hosting of Osama bin Laden in the 1990s, and a separate uprising in Darfur which Washington calls genocide.

* Washington's new envoy to Sudan, Scott Gration, has advocated more engagement with Sudan, and has visited the country on several occasions. Diplomats say he fears isolating Khartoum would hinder progress on peace in Darfur and the south.

* Sudan has been under U.S. economic sanctions since 1997 and accuses Khartoum of supporting terrorism.

* Washington bombed a pharmaceutical factory in Sudan in 1998 in retaliation for bomb attacks on its embassies in Kenya and Tanzania, saying the owner had ties to bin Laden.

* Sudan began oil production in the 1990s mostly with the help of Chinese firms, despite U.S. sanctions. Output is now over 500,000 barrels per day.

* Even as the north-south conflict was coming closer to resolution, ethnic and politically motivated fighting flared in Darfur from 2003. The United Nations estimates 300,000 have died due to the conflict and more than 2 million have been driven from their homes. Sudan says the death toll is far lower.

* The International Criminal Court issued an arrest warrant for Sudanese President Omar Hassan al-Bashir this year for war crimes in Darfur, further isolating Khartoum.

* The warrant was partly blamed for a breakdown in progress in implementing the north-south peace deal including delaying elections until April 2010. The south, under the 2005 peace deal, gained semi-autonomous status and is due to vote on secession in 2011.

(Writing by Opheera McDoom)