Iraqi Prime Minister Nouri al-Maliki made the comments in an address Wednesday, one day after a string of coordinated bombings killed 127 people in Baghdad.
Prime Minister Nouri al-Maliki was among the top officials asked to testify before parliament to explain how bombers were again able to penetrate the capital. There have been three big attacks in Baghdad since August.
Members of parliament accused the government of failing to provide adequate security and many Iraqis complained on TV that wrangling politicians bore responsibility for the deadly carnage.
During an angry parliament debate, parliament speaker Iyad al-Samaraie said he been "unable to question a single security official," about Tuesday's events, despite his position.
Prime Minister al-Maliki called on Iraqis to show unity in the face of the threat.
He says that he is calling on all political factions, and every segment of the Iraqi population to show more unity and more harmony to confront the major threat facing the country and supported by malevolent forces, with logistical support and technical experience, and obvious intent. They want to return the country, he says, to chaos and sectarianism, and to marginalize their opponents. He also warns politicians not to exploit the bombings for political gain in the upcoming elections.
No one has claimed responsibility for Tuesday's bombings, but security officials again blamed militants from al-Qaida in Iraq and members of former Iraqi leader Saddam Hussein's outlawed Ba'ath party.
Interior Minister Jawad al-Bolani, who is responsible for Iraqi security forces, insisted that he would not evade responsibility for what took place, and will testify before parliament:
He says that he is ready to appear before parliament and provide information about the security situation to legislators and to the people. He adds that the system of checks and balances gives parliament the right to perform this role, even if some legislators have hindered the process.
Tuesday's attacks targeted Iraq's new finance ministry building, the labor ministry and a courthouse. More than 100 people were killed and more than 400 were also wounded.
Looking pained, but trying to sound optimistic, Iraqi President Jalal Talabani pleaded with politicians to bury their differences and to carry on with the process of holding parliamentary elections, now set for March 7.
He says that it is urgent that all the various factions unite in order to strengthen the democratic process and to hold successful parliamentary elections, that will result in a new parliament, capable of running the country.
In fresh attacks Wednesday, Iraqi police say two roadside bombings in northern Baghdad killed four people and wounded 18 others.
Both the Iraqi government and US military have warned of a rise in attacks in the run up to Iraq's general elections, which authorities are gearing up to hold on March 7.