WASHINGTON (AP) — Wisconsin Sen. Ron Johnson says President Donald Trump stopped him from telling Ukraine's president that U.S. military aid would be forthcoming, actions now at the heart of the Democrats' impeachment inquiry.

The Republican senator told reporters Friday in Sheboygan that he realized he "had a sales job to do" after Trump blocked his suggestion, according to the Milwaukee Journal Sentinel.

Johnson made several visits to the Eastern European ally this year with the election of President Volodymyr Zelenskiy.

He told reporters in Washington last week that he briefed Trump about those visits and largely stood by Trump's actions in the Ukraine matter.

Democrats are investigating whether Trump engaged in a quid-pro-quo by withholding military aid while pressing Ukraine to investigate his rival, Democratic presidential hopeful Joe Biden.