US president Joe Biden lauded the sacrifice of generations of American troops who died fighting for their country as he marked Memorial Day with a traditional wreath-laying ceremony at Arlington National Cemetery.

Israel has marked its Memorial Day for fallen soldiers and victims of militant attacks against the backdrop of some of the deepest political divisions in its history and soaring tensions with Palestinians.

Hecklers interrupted Israel’s Prime Minister for several minutes during a Memorial Day address in which he called for unity, laying bare the country’s internal divisions even as it mourns its dead.

Israel has honoured its soldiers and civilians killed in wars and militant attacks, with air raid sirens wailing nationwide for two minutes and citizens observing a moment of pause for Memorial Day.

Arnold Schwarzenegger and Reese Witherspoon were among the US stars marking Memorial Day. The federal holiday, observed annually on the last Monday in May, honours military personnel who died in the line of duty.