Lobby group the Confederation of British Industry have produced a report claiming controversial London night flights must be protected.
The Government is currently carrying out a consultation into the impact of night flights.
A spokesperson for the DfT said no decision has yet been reached:
"We welcome the response to this consultation from CBI. The Government recognises that noise disturbance from aircraft flying at night is the least acceptable impact of airport operations on local residents.
"At this stage we are gathering evidence on what might be feasible and have taken no decisions yet on our preferences.
"We will be consulting on specific proposals later this year once we have assessed the evidence received from this consultation."
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