BAGHDAD, Iraq (CNN) -- Five Russian Sukhoi fighter jets arrived Saturday in Iraq, the first of 25 warplanes expected to be delivered under a contract agreed to by Moscow and Baghdad, the Ministry of Defense said in a statement provided to CNN.
The announcement follows a comment by Prime Minister Nuri al-Maliki that militant advances might have been avoided if Iraq had had proper airpower, in the form of fighter jets that Iraq has been trying to get from the United States for some time.
"I'll be frank and say that we were deluded when we signed the contract" with the United States, al-Maliki told the BBC in the interview last week, which was released Friday.
Iraq has now turned to Russia and Belarus to buy fighter jets, he said. "God willing, within one week, this force will be effective and will destroy the terrorists' dens," he said.
Al-Maliki's statements about the need for air support came as American and Arab diplomats told CNN that the United States is unlikely to undertake any military strikes against the militant group, the Islamic State of Iraq and Syria, and its allied fighters before a new government is formed in Iraq.
U.S. officials were quick to reject al-Maliki's complaints. U.S. fighter jets have not been slow in coming, Pentagon spokesman Rear Adm. John Kirby told CNN's "The Lead."
The first two promised F-16s "weren't expected to be delivered until the fall, which is still months away," Kirby said. "And we were in the process of working towards that delivery. In fact, those contractors that were at Balad Airfield that had to be evacuated because of ISIL advances were in fact setting up the logistical base for us to begin to deliver those F-16s." (ISIL, short for Islamic State in Iraq and the Levant, is another name for ISIS.) He added that the militant group's progress "couldn't have been stemmed through the use of two particular fighter planes."
And State Department spokeswoman Marie Harf told CNN's "The Situation Room," "This kind of blame of others on the outside is quite frankly part of what's gotten Iraq into the situation it's in today. It's helped create the crisis. When we left Iraq, we gave the Iraqis the ability to create a better future. And unfortunately, leaders across the spectrum didn't step up and take the opportunity. They blamed others and didn't bring the country together."
Kurdish authorities restrict families' return
Iraq's semiautonomous Kurdish region put tight restrictions on the border crossings used by Iraqis fleeing ISIS militants and airstrikes in the northern city of Mosul on Saturday, raising fears of a humanitarian crisis as some desperate families may be left with nowhere to go.
The Kurdish regional government's decision to first close the border crossings and then reopen them with restrictions came on the same day Iraq's security forces went on the offensive, carrying out airstrikes in Mosul and fighting to take back Tikrit from ISIS fighters.
The offensive appeared to mark a turn for Iraqi security forces, which were routed by ISIS fighters this month during a lightning advance that saw the al Qaeda offshoot seize large swaths of northern and western Iraq.
State media and a local tribal leader reported that Iraqi forces had retaken the city of Tikrit, hometown of the late dictator Saddam Hussein.
Sheikh Khamis al-Joubouri, a key tribal leader in Tikrit, told CNN that the Iraqi security forces entered the city supported by special forces and fighters from among the local tribes, and had gained control.
He said ISIS fighters retreated in the direction of Kirkuk and the province of Nineveh.
But a combatant told a CNN freelance reporter that ISIS fighters remained in control of Tikrit, though there were fierce clashes in an area about 20 kilometers (12 miles) from the city center, toward Samarra.
State-run Iraqiya TV reported that the Iraqi army and volunteer militia groups had cleared ISIS fighters from the city, having advanced on the city from four directions.
Sabah Numan, a Counter Terrorism Unit spokesman, told the station that 120 militants had been killed and 20 vehicles destroyed in a large-scale operation that began Saturday morning.
He did not provide any evidence of the claim, and CNN cannot independently confirm the reports.
Sunni tribes wade into fight
Al-Joubouri said that the tribes were not aligned with the government or with ISIS and had stayed out of the fight until now.
But, he said, when ISIS fighters who arrived in Tikrit robbed banks and carried out executions, as well as bringing the local economy to a standstill, the tribal leaders offered their help to the Iraqi security forces poised outside the city.
The tribal leaders shared their knowledge of the city, including routes and known ISIS positions, he said.
On Friday, Human Rights Watch reported the discovery in Tikrit of two mass graves believed to contain the bodies of Iraqi soldiers, police and civilians killed by ISIS and its militant allies.
Iraq's military spokesman, Maj. Gen. Qassim Atta, told reporters Saturday that Iraq's forces had regained the upper hand against ISIS and were now being supported by the tribes.
"We are advancing in all our fights," he said.
As part of that fight, Iraqi security forces broke up a terror cell in the predominantly Sunni neighborhood of al-Amiriya in eastern Baghdad, the Ministry of Defense said. Nine people were arrested following a raid Friday on a Sunni mosque, where the ministry says security forces uncovered a cache of weapons and bombs.
After being interrogated, those detained admitted they planned to carry out attacks during the holy month of Ramadan, which begins Sunday, the ministry said.
Iraq's air force carried out a series of airstrikes on the city of Mosul, according to a senior Iraqi military official.
The airstrikes targeted four locations inside Iraq's second-largest city, including ISIS headquarters, said Mazen al-Safaar, a traffic director in Mosul.
But a doctor said the airstrikes also hit Mosul's administration building and the Old City's shopping district.
At least seven civilians were killed and two were wounded in the airstrikes, according to Dr. Salaheldin al-Naimi, the director of the health administration.
Hundreds of thousands fled when Mosul fell to ISIS almost three weeks ago. Many headed for Kurdish-controlled areas.
Mass graves, executions
In addition to the alleged executions in Tikrit, reports continue to emerge of atrocities committed by both sides.
Human Rights Watch, citing displaced residents and local activists and journalists, said Saturday that ISIS fighters kidnapped at least 40 Shiite Turkmens, dynamited four Shia places of worship, and ransacked homes and farms in two Shia villages just outside Mosul.
The few Sunni villagers who remained in Guba and Shireekhan told those who fled that at least some of the kidnapped Turkmens had been killed, the rights group said. However, they had not seen bodies and could not give more information.
ISIS destroyed seven Shia places of worship in the predominantly Shia Turkmen city of Tal Afar, about 50 kilometers (30 miles) west of Mosul, earlier in the week, Human Rights Watch added, citing local sources.
"The ISIS rampage is part of a long pattern of attack by armed Sunni extremists on Turkmen and other minorities," said Letta Tayler, senior terrorism and counterterrorism researcher at Human Rights Watch. "The killing, bombing, and pillaging threatens to displace entire communities, possibly forever."
On Friday, Amnesty International said it had gathered evidence pointing to a pattern of "extrajudicial executions" of Sunni detainees by government forces and Shiite militias in Tal Afar, Mosul and Baquba.
"Reports of multiple incidents where Sunni detainees have been killed in cold blood while in the custody of Iraqi forces are deeply alarming," said Donatella Rovera, Amnesty International's senior crisis response adviser, who is in northern Iraq.
"The killings suggest a worrying pattern of reprisal attacks against Sunnis in retaliation for ISIS."