US Vice President Joe Biden fell awkwardly while attempting to dismount his bicycle after a weekend ride in Cape Henlopen State Park near his seaside home in Delaware, but he was not injured.

"I got my foot caught [in the toe clips]," he told reporters as US Secret Service agents promptly helped him.

Mr. Biden, 79, and first lady Jill Biden were nearing the end of a morning bike ride when the President decided to peddle over to a crowd of well-wishers gathered beside the trail.

As he attempted to dismount, the President, wearing a helmet, evidently fell on his right side and rolled onto his back before being pulled up.

He instantly regained his composure and spent many minutes conversing with those who had gathered to watch him cycle.

Mr. Biden required no medical attention and was "fine," according to a White House statement.

The Bidens celebrate their 45th wedding anniversary with a long weekend at their Rehoboth Beach residence.