The move from Monday came days after the boss of the group that runs Inverness Airport said the service was “hanging by a thread”.
But British Airways said flights were available to book from the end of February.
An aviation source said: “It was just not sustainable to keep the route operating in a period of extremely low demand.”
A BA spokesperson said: “Like other airlines, due to the continuing coronavirus pandemic we are operating a reduced and dynamic schedule.
"The route to Inverness is only temporarily suspended.”
Inverness airport general manager Graeme Bell said: “While we are disappointed, we appreciate that the aviation sector as a whole is once more facing an extremely challenging period, with the rapid spread of the Omicron variant impacting the demand for aviation services.
“This route provides a direct link between the Highland capital and one of the world’s leading aviation hubs.
"We hope that the recent easing of travel restrictions will allow people to plan their travel with more confidence and look forward to welcoming a full schedule of flights when the service is reintroduced.”
Highlands and Islands Airports Limited managing director Inglis Lyon had told MPs on Monday of his fears for the route.
He told the Scottish affairs committee at Westminster: “The biggest challenge that we have just now is not so much with the local domestic inter-island traffic, but about retaining the link between the capital of the Highlands and London Heathrow.
"That is an essential piece of business for the Highlands to retain, especially as we were successful in attracting it – now we have got to retain it.
"These things hang by a thread when the industry is under the pressure that it is currently under, in terms of aircraft availability, profitability and eye-watering losses over the last two years.
"Marginal routes like these come under a great deal of pressure.
"It is very important, and hopefully the Hendy [Union Connectivity] review will point towards slots like those that are used for remote regions such as ours in the Highlands and Islands being retained at London Heathrow.”
British Airways resumed flights on the route in 2016 after an 18-year gap.