The United States is developing a "new system for international travel" that will include contact tracing for when it eventually lifts travel restrictions that bar much of the world's population from entering the country, a senior White House official said on Wednesday.

White House coronavirus response coordinator Jeff Zients told the U.S. Travel and Tourism Advisory Board the administration does not plan to immediately relax any travel restrictions citing COVID-19 Delta variant cases in the United States and around the world.

Reuters first reported early in August that the White House was developing vaccine entry requirements that could cover nearly all foreign visitors. The White House previously confirmed it was considering mandating vaccines for foreign international visitors.

"The American people need to trust that the new system for international travel is safer even as we - I mean at that point - we'll be letting in more travelers," Zients said on Wednesday, adding it will eventually replace existing restrictions.

"We are exploring considering vaccination requirements for foreign nationals traveling to the United States," Zients said.

Commerce Secretary Gina Raimondo said at the same meeting that the spike in COVID-19 cases is preventing lifting international travel restrictions. "We want to move to a metrics-based system," Raimondo said. "Before we can do that, we have to get a better handle on the domestic situation, which requires us to get everyone vaccinated."

Zients said the new plan would replace the current restrictions and would be "safer, stronger and sustainable." He did not lay out specific metrics for when the administration might relax restrictions.

"Vaccination rates matter here at home and other countries," Zients said, urging travel companies like airlines to quickly mandate employee vaccines.

Some industry officials fear the Biden administration may not lift travel restrictions for months or potentially until 2022.

The extraordinary U.S. travel restrictions were first imposed on China in January 2020 to address the spread of COVID-19. Numerous other countries have been added, most recently India, in May.

The administration wanted to lift travel restrictions "as soon as we can," Zients said.

Contact Tracing

Zients said the new system will include collecting contact tracing data from passengers traveling into the United States to enable the Centers for Disease Control and Prevention (CDC) to contact travelers if exposed to COVID-19.

The Trump administration in 2020 blocked an effort to require airlines to collect contact tracing information from U.S.-bound international passengers after some senior administration officials cited privacy concerns.

Zients said they want the new system to be "ready to press go on" when it is safe to lift restrictions. "We get the importance of this," Zients said.

The United States currently bars most non-U.S. citizens who within the last 14 days have been in the United Kingdom, the 26 Schengen countries in Europe without border controls, Ireland, China, India, South Africa, Iran and Brazil.

The United States separately bars non-essential travel by most non-U.S. citizens at U.S. land borders with Mexico and Canada.

Critics say restrictions no longer make sense because some countries with high rates of COVID-19 infections are not on the restricted list while some countries on the list have the pandemic under control.