Iraqi Troops Strike Back In Tikrit Offensive

Thousands of Iraqi troops backed by tanks, warplanes and helicopter gunships have launched their biggest counteroffensive yet against ISIS militants in Tikrit.

It comes as the jihadists declared they were establishing a "caliphate", or Islamist state, in areas they control in Iraq and Syria.

ISIS ordered Muslims in territory from Aleppo in northern Syria to Diyala in eastern Iraq to "obey" and swear allegiance to the group's leader Abu Bakr al-Baghdadi.

There have been conflicting reports as to just how much headway the Iraqi military has made in its advance on Tikrit - the home town of Saddam Hussein which fell to the insurgents on June 11.

Following two weeks of demoralising defeats, the military has claimed to have regained control of the northern city, but the rebels have insisted they are still in charge.

A provincial official told the AP news agency that the insurgents retained control of most of the city, and fighting is concentrated in the northern neighbourhood of Qadissiyah.

As the "large military operation" started, Staff Lieutenant General Sabah Fatlawi warned the insurgents they had two choices: "Flee or be killed".

Witnesses reported heavy clashes as troops moved in from the west.

Troops in helicopters landed at a strategically located university campus, with sporadic clashes reported throughout the day.

Prime Minister Nouri al Maliki's security spokesman said warplanes were targeting insurgents there.

Lieutenant General Qassem Atta said security forces were also now in full control of a key road from Baghdad to Samarra, between the capital and Tikrit.

He said there was coordination with the US, which has deployed special operations forces to Iraq, over "studying important targets", without elaborating.

Also on Sunday, fighters backed by the Kurdish Peshmerga force were advancing on the village of Basheer, south of Kirkuk, which was taken over by militants during their offensive.

Sky's Senior Correspondent Michelle Clifford, who is in Baghdad, said if the recapture of Tikrit is true, "it would not only be a strategic but a symbolically significant victory".

"The government is desperate to portray this as a victory because of the humiliating capitulation by the Iraqi forces in the early days of the insurgency," she added.

Meanwhile, British Foreign Secretary William Hague has called on Iraq's political leaders to form a "more inclusive government", as the new parliament prepares to convene on Tuesday.

World leaders have insisted on a political settlement among Iraq's Shia Arab, Sunni Arab and Kurdish communities.

Top Shia cleric Grand Ayatollah Ali al Sistani has also called for unity in Iraq.

Mr al Maliki, who has publicly focused on a military response to the crisis, has acknowledged that political measures are also necessary.

On Saturday, Russia's deputy foreign minister Sergei Ryabkov said in Damascus: "Russia will not remain passive to the attempts by some groups to spread terrorism in the region.

"The situation is very dangerous in Iraq and the foundations of the Iraqi state are under threat."

Baghdad has agreed to buy more than a dozen Sukhoi warplanes from Russia and Belarus in a deal that could be worth up to $500m (£295m).

Iraqi state TV quoted Lt Gen Atta as saying Sukhoi jets had arrived, without specifying how many.