DHS Lowers Terror Alert Level From Red to Orange for Inbound Flights From UK to U.S.

As the U.S. government continues to adjust the list of things that airline passengers can carry, Homeland Security Secretary Michael Chertoff reassured Americans that things would only go so far.

"I don't see us moving to a total ban on hand baggage at this point," he said Sunday on ABC's "This Week."

The Transportation Security Administration announced new rules Sunday giving airline passengers permission to carry up to 4 ounces of liquid nonprescription medicine. TSA had previously banned all liquid medications.

Get more coverage at the Homeland Security Center.

TSA also said all passengers will be instructed to remove their shoes during security checks. The shoes have to be placed on an X-ray belt for screening before passengers can put them back on. Until now, the agency had strongly suggested putting shoes on the screening belt but hadn't required it.

Later Sunday, the Homeland Security Department reduced the threat level from red, for "severe," to orange, for "high," for flights from Britain bound for the United States. All other flights operating in or destined for the United States remain at orange.

"The security measures already taken have allowed us to address an imminent threat of attack for flights between the United Kingdom and the United States," Chertoff said in a statement. "Let me be clear: This does not mean the threat is over. The investigation continues to follow all leads.

"In particular, we are remaining vigilant for any signs of planning within the U.S. or directed at Americans," Chertoff said.

The eased restrictions on medicine and the mandatory shoe removal were among several measures ordered Sunday in response to the thwarted terror plot involving airplanes bound from Britain to the U.S.

The alleged conspirators had planned to blow up as many as 10 planes flying from Britain to the U.S. using liquid explosives, which TSA's security equipment cannot detect in carry-on luggage.

In other measures, TSA said it would let flyers carry treatments for low blood sugar, including glucose gel for diabetics; solid lipstick; and baby food. But it said all aerosols are prohibited.

On Saturday, the TSA added mascara to the list of banned items, which includes baby teethers containing gel or liquid, children's toys containing gel and gel candles.

Chertoff said the government was putting "less emphasis on the nail clippers and the nail scissors" and more on training additional screeners "specifically to look for modern-type detonation equipment that might be concealed in baggage."

He said a ban on carry-on luggage was "unlikely at this point."

"I think that we can do the job with our screening, training and our technology without banning all carry-on luggage," Chertoff said on "FOX News Sunday." "And we don't want to inconvenience unnecessarily."

Airport travelers also should expect to see broader use of police-trained sniffing dogs, TSA said, along with random gate inspections and bag searches. But the TSA is limited by law to 45,000 screeners at the 450 commercial airports.

TSA chief Kip Hawley said the latest changes were based on feedback from security officers and the public.

"We are maintaining the same level of security while clarifying interpretations in the field," he said Sunday. "These tweaks are aimed at making a smoother process at the checkpoint."

Visit FOXNews.com's Homeland Security Center for complete coverage.