The Capitol Hill newspaper called McCain's decision another indication the Arizona senator is distancing himself from Bush as he campaigns to succeed the president in the Oval Office.

The McCain campaign had no comment on the report but the National Republican Congressional Committee confirmed McCain would not attend the June 18 event in Washington, The Hill said.

"We understand that Senator McCain has a very busy schedule and cannot make it, but we look forward to honoring him next year at our 2009 President's Dinner," said NRSC spokeswoman Rebecca Fisher.

Citing a source familiar with McCain's schedule, the newspaper said the candidate is expected to be in Texas June 18.

McCain, who has frequently noted his support for Bush, has also been emphasizing his differences with the president, as the Democratic Party argues that McCain presidency would be tantamount to a third term for Bush.