Mayor Bill de Blasio may be on vacation, but he cannot get away from criticism that he does not pay his fair share when it comes to the MTA.

An ad in Thursday's Daily News, seen below, comes courtesy of the Transport Workers Union, and does not fail to poke fun at the mayor's Rhode Island getaway, while slamming him for leaving the city during the so-called "Summer of Hell" on the city's transit system.

A fake greeting penned to New Yorkers from de Blasio has him boasting of beaches and lobster dinners while denying commuters some of City Hall's $4 billion surplus for track repairs, because they are not "wealthy campaign donors."

The union has been pressuring de Blasio to foot some of the bill for the MTA's action plan to save the subways.

The mayor left for vacation earlier this week, just a month before New Yorkers hit the polls and vote in the primaries.

De Blasio is set to go head-to-head with rival Sal Albanese at a debate on NY1 on August 23 at 7 p.m.

The mayor is expected to return to the city Friday.