With travel costs expected to continue rising in 2009, companies are looking for ways to reduce business trip budgets, an industry study shows.

According to the National Business Travel Association, business travel costs will increase by up to eight percent in the coming year, the Alexandria, Va.-based trade group reported this week.

As a result, the frequency of business trips is expected to decline as companies cut back on travel budgets to save cash.

"In some companies, we are already seeing major cutbacks in travel," Kevin Maguire, the group's president and CEO, said in a statement. "Across the board, we can expect to see some changes in the way travel is managed to further maximize value," he said.

Companies are expected to reduce non-essential travel and clampdown on out-of-policy spending, the report said.

The report is based on an online survey of U.S.-based travel buyers conducted between September and October, as well as aggregated data from earlier surveys.