Experts have told U.S. lawmakers the international community needs to act quickly to impose sanctions on Sudan's government in Khartoum in response to the situation in Darfur.

The debate over Sudan sanctions comes as the United States works on the separate effort to gather enough support at the United Nations for a strong resolution on Iran.

At Tuesday's hearing of the House of Representatives Subcommittee on National Security, Emerging Threats and International Relations,  Congressman Christopher Shays asked:

"Do you believe that in order to achieve our objectives in both Iran and the Sudan that we will need to have a targeted embargo program?"

"We're at a critical moment with regard to Sudanese sanctions and the ability to send a clear message to the government in Khartoum that the international community now means business, enough is enough," explained George Lopez, a professor at the Joan Kroc Institute for International Peace Studies.

Earlier discussions of Sudan sanctions, says Lopez, allowed the Khartoum government to use the new Comprehensive Peace Agreement for southern Sudan, signed in 2005, as a bargaining chip to avoid punitive measures.

Lopez says it should be clear to all that the situation in Darfur is separate from the one in the south, and that the world needs to impose sanctions on Khartoum now.

"Targeted sanctions on the leadership of the Khartoum government and others involved in the genocide are absolutely warranted, but they do not need to be calibrated contemporaneously with what is going on politically," said Carne Ross, a former British diplomat. "You can't just punish, you also have to encourage a political solution to what is going on in Darfur, but I think they should be threatened with sanctions and if they don't comply those sanctions should be imposed."

Robert Zoellick

The latest U.S. diplomatic efforts on Darfur sent Deputy Secretary of State Robert Zoellick to Abuja, Nigeria trying with British help to salvage talks involving three Darfur rebel factions and the Khartoum government on a settlement.

U.S. Ambassador to the United Nations, John Bolton referred to these efforts Tuesday.

"There are three possible outcomes to Abuja," said Bolton. "One is a peace agreement that the parties comply with fully. The second is a peace agreement that most comply with but some do not. And the third is either no agreement, or an agreement that everybody signs and nobody complies with."

John Bolton (file photo)

Bolton says what the U.S. and others are able to do regarding the AU peacekeeping operation, its transition to U.N. supervision, and the delivery of humanitarian aid, all depend critically on the outcome.

White House spokesman Scott McClellan told reporters Tuesday that President Bush phoned Sudan's President Omar Bashir, asking him to send Vice President Taha, who left Abuja, back to help achieve a final agreement on Darfur.