Airports operator BAA has set out the reasons why it thinks its shareholders should reject the £8.75bn ($16bn) takeover bid from Spain's Ferrovial.
BAA plans to invest £9.5bn in its three London airports
BAA said it was ideally placed to take advantage of growth in air travel and had a "first-rate" management team.
Its comments came as Ferrovial said it might be willing to raise its offer for BAA slightly - if it could examine the UK firm's books.
BAA runs seven UK airports, including London's Heathrow and Gatwick.
A consortium headed by Ferrovial first approached BAA with the offer of a possible 810-pence-per-share takeover in March. But after BAA rejected the move, Ferrovial launched a hostile bid in April at the same price.
BAA also rejected a 870-pence-per-share offer from a consortium led by Goldman Sachs in April.
Ferrovial accompanied an announcement of a 44% rise in first-quarter profits with a statement that it might add "a small increase" to its offer if it was allowed to examine BAA's finances.
Explaining its defence against the Ferrovial bid, BAA said it was in a prime position to take advantage of the ongoing growth in the global air market.
It added that the value of its three London airports - Heathrow, Stansted and Gatwick - was growing rapidly, and that the skills it developed at these airports were being used to improve profits at its other sites.
BAA'S UK AIRPORTS
"It's not the right time. It's not the right price," said BAA chief executive Mike Clasper of the Ferrovial offer.
BAA chairman Marcus Agius said the offer took into account neither the value generated by BAA's airports currently, nor their "exceptional" future opportunities.
"The BAA board is determined that neither they nor anyone else should be allowed to buy BAA on the cheap," he said.
Also on Wednesday, BAA promised a £9.5bn investment programme in its three London airports, Heathrow, Gatwick and Stansted, over the next 10 years.
BAA said passenger numbers at the three airports were set to rise by 3% a year for the next decade.