Former Vice President Joe Biden canceled a planned appearance in Illinois this week because he is sick and "under doctor's orders not to travel," according to state Democrats.

"Everyone who knows Vice President Biden knows that he gives our party and our country his all, but unfortunately he is sick and is under doctor's orders not to travel," Illinois Democratic County Chairs' Association President Doug House said in a statement posted to Facebook Tuesday night.

Biden, 75, was scheduled as a keynote speaker for the Illinois Democrats County Chairs' Association brunch in Springfield, Illinois. The event kicks off Democrats' Day at the Illinois State Fair.

"The cancellation is of course disappointing, but it is clear that the circumstances are simply unavoidable," House said.

House added, "We all hope he gets well soon and I'm sure he'll be back campaigning for Democrats in Illinois and across the country in no time."

A spokesman for Biden said the former vice president is simply under the weather and will "be fine in a few days." The spokesman would not comment on the record about Biden's condition.

Biden has been crisscrossing the country campaigning with Democrats candidates ahead of the midterm elections but also fueling speculation that he'll seek the Democratic presidential nomination in 2020.