ATHENS, Greece — Cash-strapped Greece is planning steep increases in ticket prices for ancient sites and museums, which travel agents say could hit the country's key tourism industry.

The Culture Ministry wants to raise the ticket for the Acropolis from 12 euros to 20 euros, and to double entry charges for other popular sites and museums — which all together attracted more than 6 million visitors in January-June.

The leftist-led government says current charges are "unacceptably low."

It argues additional revenues could offset austerity measures demanded by international bailout creditors, such as higher taxation on all private education.

The new prices would apply from April-November 2016, with a 50 percent discount for the rest of the year.

The federation of Greek travel agents said Wednesday the hike would drive tourists away.