The phrase "an official source" is correct and usable in written English.
It can be used when referring to a credible or authoritative origin of information, often in contexts like news reporting or research.
Example: "The information was confirmed by an official source, ensuring its accuracy and reliability."
Alternatives: "a credible source" or "an authoritative source".
Syria's state news agency, SANA, citing "an official source," said that Mr. Morsi's ouster proved "the incapacity of the forces of political Islam to manage the state".
It has still not been confirmed by an official source whether he is an actual staff member or an odd choice in stock photography.
The Times of India quoted an "official source" confirming that the "government is exploring the possibility of India hosting the Olympics".
United States Naval Observatory (USNO), in Washington, D.C., an official source, with the U.S. National Institute of Standards and Technology NISTT; formerly the National Bureau of Standards), for standard time in the United States.
The Saudi news agency, citing an "official source," said that the recall of the ambassador and the closings were the result of "unjustified demonstrations" and "hostile slogans," and what the news agency said were attempts to "storm" the embassy.
Mansour, already the owner of two clubs, Al-Jazira in Abu Dhabi and Manchester City in England, issued a rebuttal through an official source who described the Spanish report as "irresponsible, lacking accuracy, credibility and professionalism".
Chosun Ilbo, a South Korean newspaper, quoted an unnamed official source as saying that US spy satellites had spotted steam rising from the main Yongbyon reprocessing plant, capable of reprocessing spent nuclear fuel rods to make weapons-grade plutonium.
The monitoring team's journey to the hamlet, Qubeir, filmed and posted online, presented the outside world with the first visual proof from a neutral official source that a horrific crime had occurred there.
In September an Iranian official source announced that Iran no longer supported condemning to death Salman Rushdie, author of the controversial book The Satanic Verses.
While precise details surrounding the crashes were unclear, the Russian new service Interfax, citing an anonymous official source, reported that minutes after the first plane went down, the second jet issued a distress signal indicating it had been hijacked.
A UK official source later said China had also been keen to explore direct trading relations with the UK after Brexit.
