BAA will be required to sell Gatwick, Stansted and Edinburgh airports, the Competition Commission has confirmed.

The commission is now considering responses to the decision, announced in a provisional document today. It is subject to final consultation, with a final report is due by the watchdog in February or March next year.

The commission is also proposing measures to ensure investment and levels of service at Heathrow, and possibly Gatwick and Stansted, to meet airlines’ needs more effectively. At Aberdeen airport, it is recommending ways to promote investment linked to rebates on airport charges.

It also intends to make recommendations to the government on a more effective and flexible system of airport regulation and airports policy.

BAA Airports Inquiry chairman Christopher Clarke said: “The most effective way to introduce competition in the south-east and in lowland Scotland is to require the three London airports and the two principal Scottish airports to be separately owned. Under the common ownership of BAA, there is no competition.”

The sale process for Gatwick has already started, and the commission requires all three airports be sold to different buyers. It remains open to views on the alternative – selling Glasgow airport.

But BAA chief executive Colin Matthews repeated his concerns of a lack of compelling evidence to sell Stansted and Gatwick.

He said: “As we said when the Competition Commission published its provisional findings in August, we do not believe that it has set out compelling evidence to support its view that selling Stansted as well as Gatwick will increase competition and we remain concerned its proposed remedies may actually delay the introduction of new runway capacity. We will continue to make our case to the Competition Commission.”

He added there was no substantial evidence to support the view Edinburgh and Glasgow would compete under separate ownership.

Meanwhile, EasyJet chief executive Andy Harrison welcomed the commission’s proposals but said they would only address part of the problem.

He said: “The simple fact is airports like Gatwick are a monopoly and simply changing the ownership will not change that fact. Until there is dramatically more airport capacity in the southeast, each of the BAA airports will continue to operate as local monopolies and monopolies rarely act in the interests of their customers.”