The Bush administration tried Wednesday to assuage concerns in the business community that international trade would be hampered by the formidable focus on homeland security.

An important mission of the proposed Department of Homeland Security will be keeping trade flowing, homeland security adviser Tom Ridge and Customs Service Commissioner Robert Bonner said.

The two officials met at the White House with a range of players -- including General Motors to groups representing trucking companies, port authorities and airlines -- with a stake in international trade.

Some are concerned about how and whether trade issues -- notably continuing efforts to improve the movement of goods across borders -- would be handled by the proposed department. They also worry whether trade concerns would take a back seat to fighting terrorists and other domestic security matters.

"We need to understand that enhancing border security and facilitating commerce must be the dual mission," Ridge said. "They are not contradictory. They are complementary," he added. "I just want to assure you and reaffirm the notion that this president feels very strongly that as we deal with border issues that we understand that there are parallel tracks down which we must move -- security and trade."

Customs oversees the nation's 301 points of entry -- including those at seaports, airports and border crossings on land. The agency plays a key role in enforcing trade provisions, collecting duties and other revenues and tracking the flow of imported goods. It also has a long history in working with business on these matters.

Bonner said the president, in a message that accompanied his plan to create the new agency, noted the need to both simultaneously improve security and "expedite the legal flow of goods on which our economy depends." The administration sent a detailed legislative proposal to Capitol Hill on Tuesday.

Some businesses also have raised concerns as to how Customs' ongoing efforts to modernize its computer systems would be affected by the proposed reorganization.

"I can tell you this: that effort will proceed. It will not slow down," Bonner said. "If anything, the modernization effort is going to be completed more quickly. I can say, I think, with absolute certainty that it is not going to slow down and it is not going to be sidetracked."

Another concern: that Customs' trade duties might be split from its security functions.

"First of all, let me say the president's proposal is that the U.S. Customs Service be transferred intact and in its entirety to the new Department of Homeland Security," Bonner said.