The phrase "approved at once" is correct and usable in written English.
It can be used to indicate that something has been accepted or authorized immediately without delay.
Example: "The proposal was reviewed and approved at once by the committee, allowing the project to move forward without any setbacks."
Alternatives: "approved immediately" or "approved right away".
So many infrastructure projects have been approved at once, including stadiums for the World Cup soccer tournament in 2014 and hydroelectric plants in the Amazon, that the government is having a hard time spending all the money allocated.
Qwest is trying to get ten states in its territory approved at once.
But when you work on a short, all of your story gets approved at once, which is kind of a blessing and a curse, given that you know as soon as your story gets approved, layout needs to get done by next week".
In theory, airstrikes can be carried out very quickly, once approved at headquarters.
Management announced plans in December to keep half for possible acquisitions and give the other $1.7 billion back to shareholders through a reverse stock split, once it's approved at a Mar. 25 meeting.
Topiramate is a sulfamate-substituted monosaccharide related to fructose approved for use as an antiepileptic agent and for the prophylaxis of migraine headaches; it is approved at doses up to 400 mg once daily for these indications [20].
Normally, once an American merger is approved at home, the European antitrust authorities fall into line, maybe adding a few conditions relating to Europe.
Once your form has been approved at the county clerk's office, you want to keep the proof in your files.
And once negotiated, these large and important proposals would need to be legislated for at Westminster, and approved at Holyrood – which itself could well take nearly a year.
When World War II broke out, he had already developed an idea for a military bridge, and in late 1940, at a conference on the problem of providing temporary spans capable of taking heavy loading, his concept of a strong but relatively light steel truss that could be prefabricated in sections was at once approved.
It was no coincidence that last month Mr Castro proposed, and his rubber-stamp legislature at once approved, fierce penalties for all who "collaborate" with the American government or, specifically, with foreign media in the effort to strangle Cuba's economy or upset its socialist system.
