The diplomat wanted to meet me at the Mingalabar restaurant.
Mr Grenell, an outspoken Trump supporter and Fox News commentator, is believed to be in line to become the president’s ambassador to Nato.
The son of Senator Prescott Bush, he was born into a wealthy and politically active family.
George Herbert Walker Bush was born on June 12, 1924, in Milton, Massachusetts.
The 50-year-old has praised Trump in the past for threatening to leave Nato, saying it made his negotiating position stronger, Bloomberg reports.
‘I think this is about NATO reform, I don’t think this is about getting rid of a NATO alliance,’ he said last year.