UPDATE 2-Boeing says certification of 737 MAX 7 is taking 'considerable amount of time'

(Adds FAA comment, congressional action in paragraphs 7-9)

CHARLESTON, South Carolina, May 31 (Reuters) - The certification of the Boeing Co 737 MAX 7 is taking a "considerable amount of time" due to new documentation requirements, but the planemaker still believes it can be certified by the end of the year, a company executive said on Wednesday.

Both the MAX 7 and MAX 10 are seen as critical for Boeing to compete against Airbus SE for orders at the larger and smaller ends of the narrowbody market.

Southwest Airlines Co was expecting to accept the first MAX 7 this year, although the airline's CEO has noted plans to put the aircraft into service could be delayed until 2024.

Boeing is readying the final "handful of documents" required by the Federal Aviation Administration (FAA) as it proceeds through the regulatory process necessary to approve the 737 MAX 7 to enter service, Mike Fleming, Boeing's senior vice president for commercial development programs, told a press briefing.

The planemaker is also "close" to receiving FAA approval to begin certification flights of its new longer 737 MAX 10, Fleming told reporters. Certification of that aircraft is still projected to occur in 2024, but will depend on when Boeing is approved to begin those flights, he said.

"The amount of documentation that we're producing on these airplanes relative to what we had to produce in the past is considerably much larger than it has been," Fleming said.

Asked about Boeing's comments, the FAA said "safety will dictate the timeline. We do not comment on ongoing certifications."

Congress in December exempted the MAX 7 and MAX 10 from a new safety standard for modern cockpit alerts that applied to all planes certified after late 2022.

The requirement had been imposed by Congress in 2020 after two fatal 737 MAX crashes killed 346 people in Indonesia and Ethiopia. (Reporting by Valerie Insinna in Charleston, South Carolina and David Shepardson in Washington; Editing by Richard Chang, Matthew Lewis and Jamie Freed)