The billions of dollars in U.S. remittances that presidential candidate Donald Trump is threatening to block to force Mexico to pay for a border wall are a financial lifeline for the Latin American country's economy and the individuals who receive the money from relatives up north.

For families across Mexico, the cash transfers help put food on the table and clothe children. They can help start a small business, add to humble cinderblock home or buy a second-hand truck to use on a farm.

So it's not surprising that the real estate magnate's proposal — to cut off remittances from the estimated 12 million Mexicans living in the United States unless Mexico makes as one-time payment of $5 billion to $10 billion — on Tuesday elicited negative reactions from many.