Washington, Apr 6 (IANS): US President Barack Obama on Tuesday criticised the plan put forward by Republican presidential hopeful Donald Trump to block remittances Mexican citizens living in the US send back home if that country does not agree to pay for a wall along the border.

Obama criticised Trump's statement by saying such a plan is "impractical" and would have "enormous" consequences, Efe news agency reported.

"The implications with respect to ending remittances, many of which -- by the way -- are from legal immigrants and from individuals who are sending money back to their families, are enormous," Obama said.

"First of all, (the plan is) impractical. We just talked about the difficulties of trying to enforce huge outflows of capital. The notion that were going to track every Western Union bit of money that's being sent to Mexico -- good luck with that," said the president in an ironic tone.

Obama was reacting to Trump's plan - -released by his campaign and published by The Washington Post on Tuesday -- to force Mexico to pay for a 1,000-mile-long wall along the US-Mexico border to keep out undocumented migrants.

However, Obama went on to say that Trump's proposal would also have "enormous" implications for Mexico's economy, and would possibly even cause more migrants to enter the US "because they can't find jobs in Mexico".

"This is just one more example of something that is not thought through and is primarily put forward for political consumption," Obama said.

Trump said in his two-page memo entitled "Compelling Mexico to Pay for the Wall" that he will block remittances sent home by Mexican citizens in the US if that country does not agree to pay for his proposed border wall.

In it, Trump reveals for the first time his strategy -- provided he wins the White House in November -- to force Mexico to pay for the 1,000-mile-long wall he has promised to build along the US-Mexico border to halt illegal immigration. The cost of the project, Trump says, would be about $8 billion.

The real estate magnate's idea is to threaten Mexico with changing the Patriot Act to cut off funds that country receives in the form of remittances from its migrants living and working in the US.

Although "it's an easy decision" for Mexico city, said Trump in the memo, he adds that Mexico would "immediately" protest that threat, since each year it receives "approximately $24 billion" in remittances from the US, most of that money being sent back home by "undocumented immigrants".

The threat to cut off the remittance flow from people illegally in the US would not be acted upon if Mexico were to agree to contribute "a one-time payment" of between $5 billion and $10 billion to help pay for the wall, according to the memo.