Francis Matthew then "admitted to the police that he carried out the crime" and "also admitted to assaulting his wife by throwing a hammer at her but he said he did not mean to kill her".
"The public prosecutor has charged the husband with premeditated murder in accordance with the federal penal code, and investigations continue in this case," the government said.
Francis and Jane Matthew had been married since 1985 and have one son. They were due to return to the UK this week to watch him graduate from university.
The pair had lived in Dubai for almost 30 years and Francis Matthew remained well connected in the wealthy Gulf state. A photograph posted on his Facebook on June 25 showed him shaking hands with Sheikh Mohammed bin Rashid al-Maktoum, the ruler of Dubai.
Friends and associates said they were astounded to hear that the genteel editor was under arrest. "He is the biggest teddy bear I know," said one family friend.
Francis Matthew studied Arabic and Islamic Studies at the University of Exeter. Before that he attended Winchester College, one of Britain's leading public schools.
He worked at the Economist before becoming editor of the Gulf News in 1995. He ran the paper's day-to-day operations until 2005 and then stepped back to do more writing but retained the title of editor-at-large.
Abdul Hamid Ahmad, the newspaper's editor-in-chief, said the newspaper was "shocked and saddened at this tragedy".
"[Francis Matthew] is a well-respected journalist, known for his keen insight into the Middle East. He was holding the position of editor-at-large at the time of the incident. Francis and Jane have played a very active role in the British expatriate community over the past 30 years."
The UAE has the death penalty but it is used relatively rarely. An Emirati woman was executed by firing squad in 2015 for stabbing an American teacher to death in an Abu Dhabi shopping mall.
The Foreign Office said: "We are in contact with the UAE authorities following the detention of a British man. We are supporting the family of a British woman following her death in Dubai. We are in contact with the UAE police."
Chris Doyle, the director of the Council for the Advancement of Arab-British Understanding (Caabu), said he had met Francis Matthew several times at conferences. "He seemed to be a very relaxed, calm individual and quite laidback," he said.