* Jailing of journalists signals fresh pressure on Jazeera
* Perceived backing for Brotherhood riles Gulf Arabs
* Channel is undaunted, says will not change policy
DOHA, July 2 (Reuters) - Al Jazeera, the Qatari-funded television station whose reporting of the 2011 Arab Spring uprisings won it millions of viewers in the Middle East, is defiant following a backlash by Arab governments that accuse it of supporting Islamists.
On June 23, three Al Jazeera journalists were sentenced by an Egyptian court for up to 10 years in jail for aiding a "terrorist organisation" - a reference to the Muslim Brotherhood that helped sweep Hosni Mubarak from power in 2011 only to be ousted itself last year in an army-backed coup.
The ruling reflected the misfortunes of the Muslim Brotherhood - in retreat across much of the Middle East after the Arab Spring turned into sectarian war - and was equally a blow to Al Jazeera and its patron Qatar.
They are under pressure in countries such as Egypt, Saudi Arabia, Bahrain and the United Arab Emirates that are intent on crushing the Muslim Brotherhood and accuse Qatar and Al Jazeera of promoting the group's activities.
The journalists denied the Egyptian charge and the verdict was denounced by press freedom advocates. Al Jazeera said there wasn't "a shred of evidence" against its staff and they had been convicted for "defending people's right to know what is going on in their world." The channel says it provides objective coverage of all opposition groups.
"Al Jazeera's editorial policy is not a subject to be bargained about or compromised on and we'll never do this now and there's no discussion about this," Mostefa Souag, the network's acting director general, told Reuters.
The channel, Souag said in an interview, is under pressure from authorities in several places because "it is the most transparent, balanced and unbiased of all Arab channels".
Founded in 1996 as part of Qatari efforts to turn economic power into political influence, Al Jazeera has often adopted the role of supporter of the dispossessed.
BROTHERHOOD CAN'T BE IGNORED
From 2011 until last year, Al Jazeera and its Gulf benefactor Qatar looked set to benefit from the new Arab order.
But a power-sharing agreement in Tunisia, where the Arab Spring began, a military-backed takeover in Egypt and a loss on the battlefield to extreme Islamist forces in Syria, rolled back triumphs that had empowered the Muslim Brotherhood.
Added to that, Al Jazeera's image as champion of the underdog changed over the course of the Arab Spring, when its coverage drew charges from some viewers that the network was supporting the Brotherhood over other opposition groups working to topple authoritarian rulers in Tunisia, Egypt and Libya.
Al Jazeera says its coverage is even handed.
"I've stopped watching Al Jazeera given the fact it no longer tells its viewers the truth. It's sowing trouble and inciting destruction in the Arab world," said Mohamed Semai, a shopkeeper in Algiers.
Al Jazeera's troubles came to a head in Egypt, after army chief Abdel Fattah al-Sisi toppled Mohamed Mursi of the Brotherhood following protests against his rule last year.
Souag said the network's offices were frequently attacked by "thugs" and authorities eventually forced them to shut in July 2013 after Mursi was ousted. Sisi was elected president in May.
Despite the closure and arrests, the channel's sister "Live" and "Egypt" stations have continued to beam live streams of Brotherhood protests and broadcast call-in shows whose participants inevitably back ousted president Mursi.
NEW MEDIA VENTURES
Qatar is also trying its hand at media diversification.
The Gulf state plans to open a London-based news channel called Al Araby, industry sources have said. A source involved in the project said the outlet will give voice to "all those who support the Arab Spring revolutions".
Efforts to build a market in the United States have faltered, however. Al Jazeera America was launched in August 2013, with 12 bureaus in major cities around the country.
Failure to capture a sizeable U.S. audience led to cost and job cuts, according to sources close to Al Jazeera. Al Jazeera America is averaging just 15,000 viewers, roughly half those who tuned in to its predecessor, Current TV, according to Nielsen.
The Qatari-funded Al Araby channel will be managed by Azmi Bishara, a Palestinian who runs a think tank in Qatar.
While it is not yet clear what response Al Araby is likely to receive from conservative Gulf Arab states, these countries have kept up strong pressure on Qatar itself to rein in its support for opposition groups around the region.
Saudi Arabia, the United Arab Emirates and Bahrain took the unprecedented step in March of withdrawing their envoys from Doha in protest at alleged Qatari interference in their internal affairs - a change diplomats say has its origins in anger at unflattering Al Jazeera coverage of their hereditary-ruled societies.
Qatar denied the charge. For his part, Souag is defiant.
"The Brotherhood is a force inside and outside Egypt and can't be ignored by the media," he said.
Even before the Arab Spring, Al Jazeera was making enemies.
In addition to Egypt, there have been bureau closures in Iraq in 2004, in Bahrain in 2010, and in Syria in the first months of what started out as a popular revolt against President Bashar al-Assad. It had to freeze operations in Saudi Arabia after Riyadh withdrew its envoy in March.
Algeria and the United Arab Emirates, both wary of Islamists, have not permitted Al Jazeera to operate locally.
Its journalists have not escaped unscathed: Sami Al Hajj, a Sudanese national, was detained while in transit to Afghanistan in 2001 and held in Guantánamo Bay until 2008. Held on suspicion of having ties with al-Qaeda, he was released without charge. In 2005, reporter Tayseer Allouni was sentenced by a Spanish court to seven years in prison for being a financial courier for al-Qaeda. Allouni denied the charges.
These days criticism of Al Jazeera comes as readily from ordinary people as from Arab governments.
Some viewers have turned to Al Arabiya, a rival channel, which reflects the more conservative view of Qatar's neighbours now in the ascendant in the region. The Dubai-based, Saudi-owned channel has provided glowing coverage of Sisi and was granted the first television interview with U.S. President Barack Obama in 2009.
(Additional reporting by Noah Browning in Dubai,; Hamid Ould Ahmed in Algiers and Maggie Fick in Cairo; Editing by Yara Bayoumy, William Maclean and Janet McBride)