Trump said the helipad would be paid for by Sikorsky, which builds Marine One.
The White House correspondents' dinner has been rescheduled for July 24, after a shooting interrupted the annual event in April.
An overnight Department of Justice filing cast Saturday's shooting on Pennsylvania Avenue as another attempted assassination of President Donald Trump.
The suspect was identified as Nasire Best, 21, of Dundalk, Maryland.
The 54-page ruling invoked the words of George Orwell and William Shakespeare, emphasizing the importance of presidential records becoming public.
President Donald Trump is defending the cost increase of his massive White House ballroom construction project.