Erbil, Iraq - Iraqi reactions to a bill recently introduced in the US Congress to arm Kurdish and Sunni forces directly has laid bare the extent of the divisions among Iraqi groups, as the country works to combat advances by the Islamic State of Iraq and the Levant (ISIL).

Members of the Iraqi parliament's Shia-majority bloc, the Iraqi National Alliance (INA), passed a resolution last week to reject a law proposed by US Republican Representative Mac Thornberry of Texas. Parliamentarians representing Kurdish and Sunni Arab-dominated blocs boycotted the vote. In late April, Thornberry, who chairs the House Armed Services Committee, introduced a bill calling to directly arm "Kurdish Peshmerga and Sunni tribal forces" with a "national security mission" in Iraq.

The bill, expected to be considered this week, stipulates that 25 to 60 percent of a $715m budget allocated for US military assistance to Iraq in its war against ISIL be directly supplied to Sunni and Kurdish forces. Last Tuesday, Democratic Senator Barbara Boxer and Republican Senator Joni Ernst followed with a bill proposing to directly arm Kurdish forces "temporarily".

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The primary reason why Kurdish and Sunni politicians boycotted the vote to reject Thornberry's bill was the slow pace of the Iraqi government's arming of local forces, politicians told Al Jazeera.

"Everyone needs to understand the situation Sunnis are facing in the fight against ISIL, and the urgent need they have for support and armament," said Faris Taha, an MP from Anbar and a member of a broader parliamentary coalition of Sunni forces known as the Union of Iraqi Forces. Sunni tribal forces have been fighting ISIL in several areas of Anbar province, including the capital Ramadi. "The government's support for tribal forces has not been at the expected level."

Some of the Sunni tribes fighting ISIL include al-Jobour, Albu Nimr and Albu Alwan. Late last year, ISIL reportedly massacred around 200 Albu Nimr tribesmen in Anbar who were fighting against them.

Iraq's government appears to have stepped up efforts in recent weeks to mobilise and support Sunni fighters in Anbar and other areas. A statement from Iraqi Prime Minister Haider al-Abbadi's office this week said "the government is working towards arming the tribal sons to fight, alongside our security forces, against ISIL gangs". The government has also reportedly opted to open the doors of the Habbaniya military base in Anbar to volunteers from local tribes to join the Popular Mobilisation Forces, a paramilitary group, and to arm those units.

Since last June, ISIL has controlled the bulk of the Sunni Arab heartland of western and central Iraq. Observers says Iraqis' reactions to the recently introduced US bills speak to their conflicting visions for the country's future.

"The differing responses illustrate that Iraq is fragmented and that all three major components are pursuing different agendas... The Kurds desire independence, the Sunnis devolution and semi-autonomous federal regions, and the Shia a strong and centralised Iraq," Mohammed Shareef, a lecturer on the international relations of the Middle East at Exeter University in the United Kingdom, told Al Jazeera.

Shia political representatives have slammed the bills as an effort to split Iraq, saying all military assistance should be delivered to the Iraqi government first and then distributed through Baghdad to fighting forces on the ground.

Those who are saying creating other forces means dividing Iraq - they are saying, in other words, that they want to rule Iraq by force and not through the convergence of interests of all sides. Atheel Nujaifi, governor of Nineveh province

"This [US] bill to offer direct military support [to Kurdish and Sunni forces] is a violation of Iraq's sovereignty and constitution," INA parliamentarian Ammar Toma told Al Jazeera. "Direct arming will only lead to more divisions and differences among Iraqis." Toma said the support among Kurds and Sunnis for direct arms deliveries from the US is due to "the delay in providing assistance to them by the Iraqi government".

Some Sunni politicians accused Abbadi of following a double standard policy citing as evidence the quick response made by the Iraqi government to arm Shia forces, that were formed according to a religious edict made by Iraq's top Shia religious leader Ali Sistani in June 2014, while dragging their feet on arming Sunni tribal forces.

Shwan Dawudi, a Kurdish member of the Iraqi parliament, expressed hope that Baghdad "has learned the lesson and [will] change its behaviour".

"We need weapons and would welcome anyone who hands it to us faster," Dawudi told Al Jazeera.

Meanwhile, Sunni and Kurdish groups charge that while the government has not provided them with much-needed assistance to combat ISIL, it has supplied tens of thousands of mostly Shia paramilitaries with weaponry. Atheel Nujaifi - governor of the Sunni-dominated Nineveh province, which is largely under ISIL's control - said the Shia politicians' decisions were influenced by the Iranian-backed Shia paramilitaries.

Nujaifi, who now lives in the city of Duhok in Iraqi Kurdistan, has tried to put together a force comprised of Nineveh volunteers to retake Mosul, Nineveh's provincial capital, from ISIL.

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"Turkey has provided arms," Nujaifi told Al Jazeera. "We are supposed to get weapons from the [Iraqi] central government, but they have not given us anything... Even salaries arrive irregularly."

So far, around 3,000 volunteers have been trained as part of the Nineveh force, and Nujaifi says there will be additional training sessions, as 10,000 people have registered. Despite the Iraqi parliament's rejection of the US bills, he would not hesitate to accept arms if the US offered them, Nujaifi said.

For Iraq to stabilise and for a measure of peace and reconciliation to take root, there needs to be a balance of power between different communities, he added.

"Those who are saying creating other forces means dividing Iraq - they are saying, in other words, that they want to rule Iraq by force and not through the convergence of interests of all sides," Nujaifi said.

US President Barack Obama's administration has already expressed its opposition to arming Sunni and Kurdish forces without involving Baghdad. As a result, some believe the current bills may not be able to pass as they stand.

"[To the Obama administration], the bill in its current form ... implies the break-up of Iraq and breaches the sovereignty of Baghdad over the state of Iraq," said Shareef, who has authored a book on US foreign policy in Iraq. "This means that a watered-down and amended bill will eventually be sent to the White House for approval."