WASHINGTON, August 27, 2010 (AFP) - US President Barack Obama congratulated Kenya Friday on its new constitution but said he was "disappointed" Nairobi had hosted Sudanese President Omar al-Bashir, a suspected war criminal.

"This historic approval and signing of the constitution is an important step forward, and demonstrates the commitment of Kenya`s leaders and people to a future of unity, democracy and equal justice for all -- even the powerful," Obama said in a statement.

"With this constitution, the people of Kenya have set a positive example for all of Africa and the world," he added, before turning his attention to the presence of Bashir, which threatened to overshadow the ceremony.

"I am disappointed that Kenya hosted Sudanese President Omar al-Bashir in defiance of International Criminal Court arrest warrants for war crimes, crimes against humanity, and genocide."

Obama reminded Kenya that it had committed itself to full cooperation with the ICC and added: "In Kenya and beyond, justice is a critical ingredient for lasting peace."

Watched by tens of thousands of his countrymen, Kenya`s President Mwai Kibaki signed the constitution into law at a colorful ceremony Friday in Nairobi`s main park.

The document, overwhelmingly approved in a national referendum earlier this month, is a pillar of reforms aimed at averting a repeat of the violence that killed more than 1,000 people following the disputed 2007 election.

But reaction abroad was one of consternation over the attendance of Bashir, one of a handful of heads of state present for the ceremony, including Rwanda`s Paul Kagame and Uganda`s Yoweri Museveni.

Bashir was indicted in March 2009 for alleged war crimes and crimes against humanity, and in July 2010 on charges of genocide, relating to atrocities committed by Khartoum`s forces in Sudan`s western province of Darfur.

BDST: 0943 HRS, August 28, 2010