The phrase "deep regret at" is correct and usable in written English.
You can use it to express sorrow over an event, especially one that has caused harm or disappointment. Example: I express deep regret at the loss of life caused by the storm.
Merkel, who called off a trip to Rome on Friday, voiced "deep regret" at his resignation.
The Russian Foreign Ministry twisted the knife by expressing "deep regret" at the "particularly lamentable" decision.
His successor, President-elect Roh Moo Hyun, also expressed "deep regret" at the North's action.
Franck Ribery has expressed his deep regret at missing out on the Ballon d'Or award on Monday night.
Their own coach, Pep Guardiola, sought no excuse, and offered no deep regret at his team running out of inspiration, or out of steam.
Prior to his departure, he spoke of how his relief was mixed with deep regret at knowing he was unlikely to see his family or country again.
This observation is uncannily relevant to my own tendency to feel deep regret as I toy with my chicken and stare wistfully at my companion's steak.
The Members of West End Synogogue, along with the entire nationwide Reconstructionist community, express our very deepest regret at the loss of Judge Mehlman.
Her son James later wrote that "her deepest regret at the end of her life" was that she had not forced Franklin to accept more refugees from Nazism during the war.
NEW YORK, 24 October 2005 - UNICEF expressed deep regret today at the passing of Mrs. Stella Obasanjo, the First Lady of Nigeria, who died on Sunday after undergoing surgery.
UNICEF Offers Sympathies After Death of First Lady of Nigeria NEW YORK, 24 October 2005 - UNICEF expressed deep regret today at the passing of Mrs. Stella Obasanjo, the First Lady of Nigeria, who died on Sunday after undergoing surgery.
