Willie Walsh, chief executive of International Airlines Group has been nominated by the governing board of oneworld, the leading global airline alliance, to serve as its chairman for the year ahead.

He succeeds American Airlines’ chairman Tom Horton, who has filled the role since December 2011.

Willie Walsh will act as “first among equals” of the chief executives of oneworld’s member airlines, starting his tenure as the alliance completes its biggest yet expansion.

TAM Airlines will join the alliance on Monday March 31st.

TAM is the leading carrier in Brazil, South America’s biggest economy and the world’s third biggest domestic market for air travel.

Its entry, alongside LAN, consolidates oneworld’s position as the leading alliance for South America.

US Airways will also join on the same day.

US Airways’ merger with oneworld founding member American Airlines creates the world’s biggest airline and giving oneworld the leading alliance position in the USA, the world’s biggest domestic air travel market.

SriLankan Airlines will follow on May 1st, as the first airline from the Indian subcontinent to join any global airline alliance.

With these recruits and the alliance’s established member airlines – airberlin, American Airlines, British Airways, Cathay Pacific Airways, Finnair, Iberia, Japan Airlines, LAN Airlines, Malaysia Airlines, Qantas, Qatar Airways, Royal Jordanian, S7 Airlines and more than 30 of their affiliated carriers – oneworld will serve almost a thousand airports in 150 countries, with more than 14,000 daily departures.