He made the remarks to reporters one day after he suggested the military could fire on members of a migrant caravan if they throw rocks at troops.
Trump has hardened his stance on immigration, and specifically a caravan of migrants traveling through Mexico as they flee violence and poverty in Central America, ahead of next week's elections, in which Trump's Republican party seeks to maintain control of the two congressional chambers.
On Monday the Pentagon said it had deployed more than 5,200 troops to the border after Trump said on Twitter he was sending the military.
Trump said on Wednesday the United States could send as many as 15,000 troops to the border, more than are in Afghanistan.
On Thursday, Trump said his administration was finalizing a plan to require asylum seekers to enter the country through legal ports of entry, although it remained unclear whether such a limitation would be legally possible. (Reporting by Roberta Rampton; Writing by Makini Brice; Editing by Jeffrey Benkoe and Dan Grebler)
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)