NAIROBI, march 02 (Associated Press) -- The U.S. stepped up its harsh criticism of Kenya, raising again the threat of sanctions against a longtime east African ally that has become riddled with infighting and allegations of corruption.

"Nothing's off the table," said Karl Wycoff, the deputy assistant secretary of state for African Affairs, referring to steps Washington is willing to take as it urges Kenya to crack down on political violence and root out corruption.

Washington's hard line against Kenya began building after the disputed 2007 presidential elections sparked ethnic clashes that killed more than 1,300 people and displaced tens of thousands more. Rivals Mwai Kibaki and Raila Odinga agreed to a internationally brokered power-sharing deal that made them president and prime minister, respectively. They pledged to work together to end ethnic disputes and overhaul the country's colonial-holdover constitution.

Two years later, however, their coalition government reamains shaky and the country is on edge. The U.S. is increasingly impatient for the government to take steps to punish those responsible for the postelection violence, crack down on corruption and amend the constitution.

"We will not hesitate to give our opinions when we feel that's what needs to be done," Mr. Wycoff said. "We will take strong actions when we think that's what needs to be done to move the reform process forward."

An anticorruption protester last month in Nairobi.
Kenyan officials have bristled at U.S. pressure. Kenyan government spokesman Alfred Mutua called the pattern of U.S. criticism and threats condescending. "Their policy is playing to the [Kenyan public] gallery, which we call activism diplomacy," he said, calling the warnings on travel bans part of "a big bully blackmail system."

The U.S. believes now is the time to push, a senior U.S. official said, in part because the U.S. enjoys wide support among Kenyans that deepened with the election of Barack Obama. Washington also sees a grass-roots move toward change among Kenyans weary of backbiting politics and scandals. And officials want to move before politicians turn back to campaigning ahead of elections in 2012.

The U.S. push in Kenya—a bastion of stability in an east Africa region that includes the war-torn states of Somalia and Sudan—contrasts with its more subtle approach toward neighbors including Ethiopia, an ally of the U.S. in its fight against terrorism that has been accused of human-rights abuses related to political violence.

"There may or may not be such windows of opportunity in other countries," the U.S. official said. "But Washington is looking at this particularly as a very unique, historic opportunity to bring about real change."

In October, Washington banned U.S. entry to Kenya's attorney general, who it said had obstructed anticorruption efforts. It has issued letters to several other officials threatening similar action.

The most recent clash between Kenya's top leaders followed two corruption scandals over the past several months. In one, an independent auditor alleged the Agriculture Ministry had sold its reserve grain to shell companies that marked it up, raising market prices as people went hungry in rural areas. In another case, about $1 million in funds disappeared from a fund for free primary education.

Mr. Odinga, the prime minister, suspended the two ministers. Mr. Kibaki reinstated them. The dispute threatened to inflame ethnic tensions: After Mr. Odinga's announcement, makeshift roadblocks—often a precursor to ethnic violence—sprang up in Eldoret, which saw some of the worst violence in 2008.

The two leaders met Sunday and said they repaired their rift, adding they remain committed to their partnership.

The government spokesman said the government is expected to hold a referendum on the new constitution by the year's end, a move toward spreading power beyond the president and establishing a more accountable system of government. "We are progressing very well," he said. "But it is not because of the U.S.'s so-called interference."