United Airlines Boeing 787-9 Dreamliner landing in London Heathrow International airport in England, UK.Nicolas Economou | NurPhoto | Getty ImagesUnited Airlines on Thursday said it plans to offer pre-flight Covid-19 testing next month for some travelers heading to London, the latest effort to get around travel restrictions and concerns about the virus.The trial will run from Nov. 16 through Dec. 11 on some flights from its hub in Newark, New Jersey, to London’s Heathrow. United will pay for the rapid molecular Abbott ID Now tests, for Monday, Wednesday and Friday departures. Travelers who don’t want to be tested will be moved to other flights “guaranteeing everyone on board other than children under two will have tested negative before departure,” said the airline.United and other airlines with sprawling international networks have struggled during the pandemic as a web of travel bans and quarantine requirements devastates demand.But carriers are increasingly turning to pre-flight testing as a potential way to avoid quarantine periods and outright entry restrictions and have urged officials to consider negative test results as a substitute for quarantines and other rules.”This patchwork of rules is confusing and discourages travel,” a group of 20 trade groups that represent companies from American Airlines to Boeing and Marriott and labor unions wrote to the Trump administration last week. “Furthermore, there are alternatives to quarantines, such as testing and screening of passengers at or ahead of departure, that can significantly reduce the risk of importation of COVID-19 and may actually be more effective due to the difficulties in enforcing compliance with quarantine requirements.”United earlier this month started offering Covid tests, which travelers pay for, to some passengers traveling from San Francisco to Hawaii. The launch coincided with Hawaii’s removal of a two-week quarantine requirement for inbound travelers if they had a negative Covid-19 test result within 72 hours.The tests ahead of the London flights will be conducted at Newark airport at a United Club lounge and customers have to make an appointment ahead of time.United said it will share feedback from customers to U.S. and U.K. government officials and said travel demand has increased when travelers have the option to test for the virus before the flight.