On January 25, 2019 U.S. President Donald J. Trump stated
"We do not need 2,000 miles of concrete wall from sea to shiny sea. We never did. We never proposed that."
CNN could not find an instance where Trump had proposed a 2,000-mile concrete wall from sea to sea.
Fact-checking Trump's speech to end the shutdown Source: CNN; see also Full Replay/Transcript: President Trump Announces Deal Reached To End Government Shutdown Source: RealClear Politics.
However, it's a very common belief that
In the run-up to the 2016 presidential election, Mr Trump promised to build a wall along the border's entire 2,000-mile length.
BBC News, 21 January 2019
I did find that on June 25, 2018 Trump stated
We gotta get that wall built, all the way across.
Speech: Donald Trump Holds a Rally in South Carolina for the GOP Primary - June 25, 2018 Source: Factba.se.
However, "all the way across" might or might not be considered by some scientific skeptics as inconclusive.
Did then U.S. presidential candidate and eventual U.S. President Donald J. Trump ever propose or "promise" constructing a border wall for the entire 2000 mile U.S.-Mexico border?