WASHINGTON (REUTERS) - United States Vice President Joe Biden will speak next month at a closely watched Democratic event in Iowa in a move likely to generate speculation about whether he might seek to run for president in 2016.

Mr Biden will speak at the "Harkin steak fry," a fundraiser named for Iowa Democratic Senator Tom Harkin. The event is to be held Sept. 15 in Indianola.

"The vice president accepted Senator Harkin's invitation to attend the steak fry this year. It has been a long-standing commitment after the vice president was unable to attend last year," a Biden aide said on Saturday.

Mr Biden has expressed interest in seeking the Democratic presidential nomination in 2016 and succeed Barack Obama as president.

But the big name on the Democratic side is former Secretary of State Hillary Clinton. Her prospects for 2016 have generated a huge buzz that she has not discouraged.

Mr Biden's decision to go to Iowa, the state whose caucuses are the first voting event in presidential campaigns, suggests he wants to show Democratic activists in the state that he is interested in running.