Washington  - President George W Bush on Monday cited the need to honour members of the military, as he remembered those killed in US wars in a service marking Memorial Day at Arlington National Cemetary near Washington.

In his last remarks as president on the holiday to remember war dead, Bush emphasized the sacrifices of those who have died in the past year in the conflicts in Iraq and Afghanistan.

"We offer a solemn pledge to persevere and to provide the security for our citizens and secure the peace for which they fought," he said to those marking the occasion at the military cemetary.

He first laid a wreath at the Tomb of the Unknowns, as a military bugler performed Taps, traditionally played at military funerals.

"It is a solemn reminder of the cost of freedom that the number of headstones in a place such as this grows with every new Memorial Day," he said. "In a world where freedom is constantly under attack, and in a world where our security is challenged, the joys of liberty are often purchased by the sacrifices of those who serve a cause greater than themselves."

More than 4,000 troops have died in Iraq and nearly 500 in Afghanistan during the conflicts there, according to US military figures.

Memorial Day, which falls on the last Monday of May each year, is marked by parades and services to remember US war dead and has also become the unofficial beginning of the US summer holiday season. (dpa)