DENVER (August 14, 2012)--Mitt Romney's campaign is blocking reporters from covering GOP vice presidential candidate Paul Ryan's first meeting with donors Tuesday night at The Venetian hotel in Las Vegas, which is expected to draw casino owner and Republican mega-donor Sheldon Adelson.

The decision to block access marks a departure from rules previously established by Romney's campaign.

Reporters usually are allowed to cover President Barack Obama's fundraisers when they are held in public venues.

A Romney aide who was not authorized to speak for the record said the event is closed to the media because it is a "finance meeting" instead of a fundraiser.

The aide said fewer than 40 people were expected to attend.

Ryan attended two fundraisers on Monday night in the Denver area where media coverage also was prohibited.