He is the third confirmed case in Britain, and the first British national to have caught the virus, the Guardian quoted government sources as saying.
On Friday, director of medical services at Singapore's Ministry of Health (MOH) said that the man had attended a private business meeting at Grand Hyatt Singapore.
READ: More than 100 people attended meeting at Grand Hyatt Singapore linked to Malaysia, South Korea coronavirus cases
"My understanding is (that) very recently, the United Kingdom also announced one case related to the same meeting,” he said.
Four other attendees of the meeting, which was held between Jan 20 and 22, have been infected with the virus, Mr Mak said. One of them is Singaporean, two are South Koreans and one is Malaysian.
While MOH said that all 109 attendees of the meeting are from the same company, Mr Mak said he was not at liberty to reveal the name of the company as the matter is still under investigation.
It has been reported, however, that the event was organised by Servomex, which describes itself as a "provider of reliable, accurate and stable gas measurements". A source has also told CNA that the event was organised by the company, which was founded in the UK and has worldwide offices.
CNA contacted Servomex's office in Singapore for comment, but the company did not respond.
The British patient, a middle-aged man, is the first case in Britain to have contracted the virus outside China, the BBC reported.
He was isolated at home prior to being confirmed positive for the virus and is being treated at a specialist infectious diseases unit at a London hospital, it added.
“The individual did not acquire (the coronavirus) in the UK,” said the country’s Chief Medical Officer Chris Whitty on Thursday.
“We are now working quickly to identify any contacts the patient has had.”
On Thursday, the Chinese ambassador to the UK said the country’s advice for its nationals to leave China was an “overreaction”.
Liu Xiaoming called for a more measured approach after Britain advised its nationals to leave China “if they can” to minimise risk of exposure to the virus.
Travellers arriving in Britain from nine countries and territories have been advised to stay at home and call the National Health Service (NHS) if they are ill within 14 days of their arrival.
The advisory, which initially only covered mainland China, has been modified to include Thailand, Japan, South Korea, Taiwan, Singapore, Malaysia, Hong Kong and Macau.
Britain’s Department of Health urged the public to call the NHS even if they are presenting mild symptoms.
“These countries have been identified because of the volume of air travel from affected areas, understanding of other travel routes and number of reported cases,” it was quoted by the BBC as saying. “This list will be kept under review.”
Two other people from the same family had previously tested positive for the virus in the UK.
British officials had warned that the country is highly likely to have cases of the novel coronavirus, which has killed 636 people and infected more than 31,000.
Only two deaths have been reported outside China, with one each in the Philippines and Hong Kong.
The epidemic, which was declared a global health emergency by the World Health Organization, is believed to have originated from a market that sold wildlife in Wuhan, Hubei province.