In tit-for-tat politics, JetBlue Airways (B6, New York JFK) has lodged a formal objection with the US Department of Transportation to codeshare application exemptions and authorisations sought by Delta Air Lines and SAS Scandinavian Airlines, asking the regulator to wait until the European Union, Italy, and Croatia provide a satisfactory explanation for their denial of JetBlue's proposed codeshare with Air Serbia.

In a regulatory filing on August 6, JetBlue seeks either a clear rationale for the denial or a commitment from European regulators to authorise its proposed codeshare with Air Serbia on US-Italy and US-Croatia routes via Serbia, an open-skies partner and member of the European Common Aviation Area (ECAA). Italy, Croatia, and the EU have indicated that the ECAA agreement does not allow such codesharing. JetBlue points out that many US and EU airlines successfully codeshare in Serbia and similar ECAA countries, highlighting an imbalance in reciprocity that JetBlue believes the DOT needs to address.

"If the EU's stance on traffic rights is accurate, DOT should reconsider granting codeshare licenses to Delta and SAS for ECAA routes and may need to amend existing approvals for US and EU carriers to ensure reciprocal treatment," it argues.

Delta and SAS are seeking authority to codeshare to Croatia, Italy, and three other ECAA countries - Bosnia and Herzegovina, Albania, and Montenegro - that are not part of the EU. Their application requests permission to display Delta's designator code on intra-European segments, including routes within the EU, Norway, and other ECAA countries where open skies agreements are in effect.