American Airlines (AAL) welcomed 150 international flights Monday as the U.S. opened its borders to non-citizens who are fully vaccinated against COVID-19.

"We're seeing fantastic demand, 40,000 customers are coming inbound to the U.S. today," American Airlines President Robert Isom told Yahoo Finance Live.

"People want to get out on the road," Isom said, predicting the surge to continue well into 2022. "There are families and grandparents that haven't seen, you know, children in a long time. Business people that really want to get out and make contact with customers, you know, it's all over the place."

New CDC guidelines require non-citizen travelers to provide proof they have been fully vaccinated against COVID-19 prior to boarding a flight to the U.S. All passengers, including U.S. citizens, are required to test negative for COVID-19 within three days of a flight's departure.

American, like other airlines provides tools on its website and app to help passengers comply with the new COVID requirements.

"It's really simple to use. It gives you great confidence that you're doing all the things you need to do. And so really I recommend for people to go out there, download the VerFly app, and we'll make sure you're going to get to where you want to go with everything you need," Isom promised.

American Airlines bookings jumped '60% from the UK'

Latin America and Europe are key to American's international recovery and bookings jumped, in September, when the Biden administration announced U.S. borders would open to foreigners. "We saw bookings increase immediately overnight by about 60% from the UK, and over 70% from South America and that kind of demand has continued on," Isom said.

Other U.S. carriers are counting on a return of international travelers to help bring them back to profitability as the airlines ramp up flights for the holidays. Isom recently told investors, "We expect the domestic leisure revenues will surpass 2019 levels in the fourth quarter and continue that trend throughout 2022. Short-haul international revenues should follow that same pattern."

American is the largest airline in the world when measured by fleet and number of total passengers but the legacy carriers and smaller airlines, regardless of size, say they need international travelers to emerge from the COVID-19 pandemic which decimated their industry.

Delta Air Lines (DAL) CEO Ed Bastian recently told Yahoo Finance the airline expects to end the year with roughly 75% of its business restored, compared to 2019.

At United Airlines (UAL) the return of international travelers promises big returns. Raymond James analyst Savanthi Syth told Yahoo Finance, 50% of United's revenue in 2019 was tied to international trips.

"If you look at their 2019 revenue, about 60% of their revenue was domestic, 40% International. But of that 60%, about 10 percentage points were domestic trips related to an international trip. So really 50, they're about 50-50, domestic International," she said.

Syth says American's international sales in 2019 ranged between 25% and 30% of total revenue. The airline plans 200 daily flights to international destinations this month and plans to raise the daily number to 300 early next year.

Isom said American is poised to take advantage of the travel rebound. "We see it coming. Domestic, especially leisure travel has been there. Throughout the pandemic we've been waiting for international to reopen, which it is now," he said adding the last piece of the puzzle is getting business travelers back in the air.

"I fully anticipate that by the end of 2022 business travel is going to be back to where it was before" the pandemic, Isom predicted. "And that's good news for American Airlines," he said with a smile.

Adam Shapiro is co-anchor of Yahoo Finance Live. Follow him on Twitter @Ajshaps

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