Updated

The United Nations on Monday paid tribute to 22 staff members killed 10 years ago in a Baghdad bombing it termed "one of the most devastating attacks" in UN history.

"Ten years ago, 22 cherished United Nations staff members and colleagues perished in a horrific attack that still reverberates in our hearts and in our memory," a statement quoted UN Under-Secretary-General for Political Affairs Jeffrey Feltman as saying.

"Our ongoing work today here in Iraq is the best possible tribute to those who perished," said Feltman, who was on a two-day visit to Iraq.

The UN held a memorial service in Baghdad on Monday for the victims of the attack.

On August 19, 2003, a suicide bomber detonated an explosives-rigged truck at the Canal Hotel in the Iraqi capital, smashing a corner of the building and killing Brazilian UN envoy Sergio Vieira de Mello and 21 others.

The bombing, along with another attack targeting the UN and the worsening security situation in country, drove heightened security measures for UN personnel in Iraq that persist to this day.

The moves are said to have reduced the mission's interactions with ordinary Iraqis.

The UN is nonetheless still active in Iraq, with staff around the country working on issues ranging from Iraqi-Kuwaiti relations, elections and national reconciliation, to Syrian refugees and Iraqis forced to flee their homes by violence.

Feltman also addressed the surge in violence that has hit Iraq this year, killing more than 3,500 people according to an AFP tally.

"Iraq's political leaders have a clear responsibility to leave no space to those who seek to exploit the political stalemate through violence and terror, and undermine a democratic Iraq," he said.