Interior minister Joseph Ole Lenku delivered the diplomatic slap when he updated reporters on a government investigation into the assault carried out eight days ago by Islamist militants on the crowded upmarket Westgate centre.
The attack, which was claimed by the Somali Islamist militant group al Shabaab whose fighters fired on shoppers and tossed grenades leaving a trail of victims of all ages, has shocked Kenya and the world.
Although Kenyan police assisted by US, Israeli and European experts are still poring over the partially wrecked mall building, Ole Lenku said the death toll from the attack still stood at 67. Five attackers were also killed.
Besides more than 50 Kenyans, citizens from Britain, France, China, Ghana, Canada, Australia, South Africa, Peru and the Netherlands were also killed.
Ole Lenku expressed Kenya's strong objections to an updated travel advisory issued by the U.S. government to its citizens urging them to "evaluate their personal security situation in light of continuing and recently heightened threats from terrorism" in the east African country.
Although he did not specifically mention tourism, the minister's comments appeared to reflect Kenyan concern over the impact the attack - and the U.S. travel advisory - could have on the country's $1 billion-a-year tourist industry.
"We are concerned by the advisory which is uncalled for, unnecessary, and unfriendly ... We believe issuing the travel advisory is counter-productive in the fight against global terrorism," Ole Lenku said.
Kenya requested that the United States, "as a friend of Kenya", lift the warning, Ole Lenku said, adding that the country remained calm though in a state of heightened security.
"There have been numerous terror attacks around the globe and traditionally, friendly countries have not done anything to increase the pain of the victim country," Ole Lenku said.
The Nairobi attack was the worst in Kenya since the U.S. Embassy was bombed in the capital by al Qaeda in 1998, killing more than 200 people, mostly Kenyans. Since then, Kenya has been seen by the West as an ally in the fight against terrorism.
The rebuke for Washington was delivered at a time when Kenya's government faced intense questions from its own public about whether it had received advance intelligence warnings of the deadly strike against the mall.
At the weekend, major Kenyan newspapers reported that the country's intelligence services had warned of a possible attack in Nairobi, with the Westgate mall as one likely target.
The reports emerged ahead of a meeting on Monday of the Kenyan parliament's defence committee which is expected to ask security chiefs how much warning they had of the assault.
Claiming the mall attack that extended into a four-day siege, al Shabaab said it acted in revenge against Kenyan troops who have been fighting it in neighbouring Somalia for two years.
'Potential terrorist threats'
"US government continues to receive information about potential terrorist threats aimed at US, Western and Kenyan interests in Kenya, including in the Nairobi area and in the coastal city of Mombasa," read the updated travel warning posted by the State Department on its website on Friday.
Ole Lenku said nine suspects were in custody over the raid, one of them arrested on Sunday. The minister declined to give any information about the suspected attackers or those arrested, saying "we do not discuss intelligence matters in public".
Addressing intense speculation that hostages were taken during the attack, and could be dead and buried in the rubble of the damaged mall, Ole Lenku said: "It is the government position that there were no hostages and we managed to rescue all the people who were in the building."
But he added this would depend on the forensic evidence.
Equally, there had been no formal reports to the police of missing persons from the attack, he said. Kenya's Red Cross had previously listed dozens of people missing.
The possibility that al Shabaab, which has carried out previous smaller gun and grenade attacks in Kenya, may be planning further high-profile strikes presents a major security challenge for President Uhuru Kenyatta, elected in March.
But the incident has also rallied foreign support for him as he faces charges of crimes against humanity at the International Criminal Court in The Hague. He denies charges of orchestrating violence after Kenya's disputed 2007 elections.
The lack of information about the attackers' identities has produced speculation that radicalised diaspora Somalis from the United States and Europe may have been involved.
Kenyan and Western officials have said they cannot confirm speculation that Briton Samantha Lewthwaite, widow of one of the 2005 London suicide bombers, had a role in the mall attack. Some survivors said they saw an armed white woman.
