Update, 1 p.m. EDT -- Spokespeople for Royal Caribbean and MSC Cruises report that Thursday's aviation strike will not impact cruise calls for Navigator of the Seas, MSC Armonia or MSC Musica.

What's the issue?
(July 13, 5:33 p.m. EDT) -- Three cruise lines made adjustments to Athens tour schedules today due to ongoing strike action in Greece. Public sector workers were involved in a three-hour strike in Greece today to protest the government's austerity measures related to pay and pensions. As ministry of culture workers were also on strike, the Acropolis and other archaeological sites were closed from 8 a.m. to noon, reports The Sofia Echo.

The next potential cruise impact could be on July 15; a strike by air traffic controllers is set for Thursday morning local time, reports the The Associated Press.

Which ports and ships were affected?
Courtney Recht, spokeswoman for Norwegian Cruise Line reported that most Norwegian Gem tours affected by the strike were rearranged to skip the Acropolis visit. "The only tour that had to be canceled was Ancient Treasures," she said.

Cynthia Martinez, who represents sister companies Celebrity Cruises and Royal Caribbean told Cruise Critic that excursion times for Celebrity Equinox and Splendour of the Seas passengers were "shuffled … around so to minimize impact to guests."

What's the cruise impact?
Looking ahead, cruise lines with ships calling in Athens on Thursday week include MSC Cruises' MSC Armonia and MSC Musica, and Royal Caribbean's Navigator of the Seas. Royal Caribbean is reporting no itinerary changes so far; we have not yet heard back from our contact at MSC Cruises.

We'll keep you posted.

--by Erica Silverstein, Senior Editor