Washington -- President Barack Obama said Friday that sanctions against Libya will target the government while protecting the people.
"We will stand steadfastly with the Libyan people in their demand for universal rights, and a government that is responsive to their aspirations," he said in a statement. "Their human dignity cannot be denied."
Obama cited the Libyan government's "continued violation of human rights, brutalization of its people, and outrageous threats" and said Libyan leader Moammar Gadhafi should be held to account.
His statement came at about the same time that he issued an executive order blocking property and prohibiting certain transactions related to Libya.
Citing "a serious risk that Libyan state assets will be misappropriated by Gadhafi, members of his government, members of his family, or his close associates," Obama declared a national emergency to deal with the threat and ordered that U.S.-based or U.S.-controlled Libyan properties and interests "are blocked and may not be transferred, paid, exported, withdrawn, or otherwise dealt in."
The declaration of emergency allowed the order to become effective at the time it was issued -- 8 p.m. ET February 25.
The order freezing assets names Gadhafi and four of his children and asks the Treasury Department, in consultation with the State Department, to identify other people who meet the criteria of the order, including people linked to human rights abuses related to political repression in Libya.
In a conference call with reporters, Under Secretary for Terrorism and Financial Intelligence Stuart Levey said that the efforts were intended to keep the Libyan regime from looting assets that belong to the people.
He said the actions were taken in coordination with other countries, including the European Union, which are considering issuing their own sanctions "in the coming week."
Exempted from the executive order are transactions with financial institutions owned and controlled by the Libyan government but organized under the laws of a country other than Libya, he said.
"We did that to minimize undue disruption to the commerce in third countries," Levey said.
Asked how much money might be affected by the freeze, he refused to cite a number but called the total "substantial by any measure."
The order appears to give an incentive to senior Libyan government officials who might be covered by the order to quit their jobs. "Those who decide not to be senior officials of the government of Libya would not meet the criteria to have their assets frozen," Levey said.
Asked whether travel privileges might also be affected, he said he expected the State Department to issue visa bans for the people identified in the order.
CNN's Scott Spoerry conributed to this story.