Memo to Sen. Tom Cotton (R-AR): It takes big bucks to run a real big city subway system.

The junior senator from Arkansas was overheard Tuesday complaining to a Republican colleague about what he called excessive funding for NYC transit in the bipartisan infrastructure proposal.

“Actually, I asked if (Senate Majority Leader Chuck Schumer) is going to gold-plate every rail in the NYC subway system,” Cotton tweeted. “He’s asking for enough money to do that.”

Cotton, a conservative Republican, was taking a pot shot at the public transit funding in the plan that Republican and Democratic moderates are haggling over.

Schumer (D-N.Y.)is unlikely to take offense at the jibe.

The Senate Majority Leader is a self-styled champion of public transit funding and often brags about his ability to bring home the bacon for the Metropolitan Transit Authority, which runs the subway system.

Republicans say the MTA and other public transit systems have already received enough rescue funds in the previous COVID-19 recovery packages.

Democrats say they are still facing huge deficits since ridership has not returned to pre-pandemic levels.

Cotton is considered unlikely to vote for the plan in any case because its passage would amount to a major victory for President Biden.