Bigwigs from Schipol Airport in Amsterdam and Chicago's O'Hare will be taking part in a discussion of the competitive challenges faced by large cities in growing their vital air links to global markets.
Mayor Boris Johnson has previously voiced his anger that any further delay in establishing a proper aviation strategy for the south east will give the advantage to continental hubs.
Schipol is expected to outstrip Heathrow in terms of passengers and flights within a decade. Last year they launched an aggressive advertising campaign, marketing itself as Heathrow's third runway.
In expanding to six runways Chicago's O'Hare has faced many of the challenges, both political and financial, that are now being faced in the south east.
Representatives from Schipol and O'Hare will be joined by Daniel Moylan, London Mayoral Adviser on Aviation Policy and the CEOs of both Heathrow and Gatwick airports.
More top news
The threat level has been raised to critical by MI5's Counter-Terrorism Analysis Centre.
Sam Allardyce has quit as manager of Crystal Palace and retired from football management.
Authorities named Salman Abedi as the suspected attacker who detonated a bomb at the Manchester Arena.