The UK's Civil Aviation Authority (CAA) on Wednesday cleared Boeing's 737 MAX model to resume flights in the country close to two years after it was grounded following fatal crashes.

The decision came hours after the aircraft was declared safe by the EASA and on a day the aircraft manufacturer announced a record annual loss for the company of almost $12 billion.

"The UK Civil Aviation Authority (CAA) has today announced that it will allow UK airlines to operate passenger flights with the Boeing 737 MAX aircraft, subject to close oversight. The ban on the aircraft operating in UK airspace will also be removed. The changes come into effect today," the CAA said in a statement.

The CAA said the decision was made based on detailed information from the European Union Aviation Safety Agency (EASA), the U.S. Federal Aviation Administration (FAA) and Boeing.

"The decision follows the approval of design modifications to the aircraft itself, how it is flown, and to pilot training.  This has included modification to the aircraft's Manoeuvring Characteristics Augmentation System (MCAS) and other key safety changes aimed at preventing further accidents. The CAA has been closely involved in this approval work and the extensive process undertaken by all involved."

The CAA said it had "full oversight" of the airline's plans including its pilot training programmes and implementation of the required aircraft modifications.

It added flights of such type into the UK may not be seen immediately as all airlines will need to go through mandated steps to return the aircraft to service.

CAA CEO Richard Moriarty said the body's decision was not one taken lightly and would not have been so "unless we were satisfied that the aircraft type is airworthy and can be operated safely".

Boeing 737 MAX models were grounded globally in March 2019 following two crashes in Indonesia and Ethiopia that killed 346 people raising questions over the certification process by the U.S. Federal Aviation Administration.

189 people were killed when Lion Air Flight 610 crashed in Indonesia in 2018 while 157 people were killed when flight ET302 crashed in Bishoftu, southeast of Addis Ababa. Both crashes involved the 737 MAX model, Boeing's best-selling model.

(With input from agencies)