Imad Moustapha, the Syrian ambassador to the US, told Al Jazeera the restrictions were "ridiculous".
"There is not a single Syrian official who has assets in the United States. This is ridiculous.
"We believe we need to engage constructively with the United States."
The order also restated the Bush administration's accusation that Syria was interfering in Lebanese affairs.
"Syria continues to undermine Lebanon's sovereignty and democracy, imprison democracy activists, curtail human rights, and sponsor and harbour terrorists," the White House said in a statement issued by spokesman Gordon Johndroe.
Syrian forces ended their 29-year presence in Lebanon under international pressure following the 2005 assassination of Rafiq al-Hariri, the former Lebanese prime minister, but the US says Syria has continued to interfere in Lebanese politics.
Damascus has repeatedly denied the US allegations.
The White House said the order expanded action taken in May 2004 when Bush issued an order banning all US exports to Syria except for food and medicine.
The 2004 order was issued mainly over Syrian support for the Hezbollah, the Lebanese opposition group, and Hamas, the Palestinian organisation.
Washington has also since blacklisted several Syrian officials.