The government is reported to be looking to hold a formal consultation on plans for a new airport in the Thames Estuary.
The BBC reports a consultation is expected to be announced in March, and that while no decisions had been made, ministers wanted to “explore all options for maintaining the UK’s status as a global aviation hub”.
Prime Minister David Cameron is said to be supportive of Mr Johnson’s alternative to expanding Heathrow, but will await the outcome of the consultation.
Mr Johnson has said the constrictions of Heathrow were becoming “ever more apparent and ever more damaging”. The present government is opposed to any expansion at Heathrow, which could lose its status as the UK’s hub airport if the Estuary plans go ahead, threatening well over 100,000 jobs.