Trump's prime-time address, scheduled for 9 p.m. (0200 GMT Wednesday) will be the Republican president's latest attempt to persuade Democrats to back his push for a steel barrier on the southern border. Amid his talk of crisis, Trump is considering declaring the border situation a national emergency, which could get him out of an impasse by enabling him to bypass Congress' mandate to approve federal spending and to build the wall without its approval. The White House has not said why the situation might constitute a national emergency.