* Uighur professor in custody since January
* Says he defends Uighur rights, denies any association with violence
* Separatism charge a serious crime in China (Adds U.S. comment, paragraphs 16-18)
By Michael Martina
BEIJING, Feb 26 (Reuters) - A prominent ethnic Uighur economist is unlikely to receive a fair trial and could face the death penalty after being charged with separatism in China's far western Xinjiang region, his lawyer said on Wednesday.
Beijing police last month detained Ilham Tohti, a professor who has championed the rights of Xinjiang's large Muslim Uighur minority. Unrest in Xinjiang has killed more than 100 people in the past year, prompting authorities to toughen their stance.
Tohti was taken after his detention to Xinjiang's regional capital Urumqi and on Tuesday his wife was notified of the charges. His case has draw concern from the United States and Europe over human rights abuses.
"To a degree, his name has already been blackened in the court of public opinion," Tohti's lawyer Li Fangping said by telephone from Urumqi, where he said he has not been allowed to see his client after a month and a half in detention.
"We'll have to wait and see if his trial will be fair. We are not feeling very optimistic."
If found guilty, Li said, Tohti was most likely to receive a sentence between 10 years and life in prison, but China's criminal code also provides for the death sentence for separatism. With strategic border regions like Xinjiang and Tibet populated with ethnic minorities, separatism is considered a serious crime.
"It includes the possibility (of a death sentence). If there are no other violent circumstances, it should be 10 years to life," Li said.
Tohti's wife, Guzailai Nu'er, has dismissed the charge as "ridiculous".
"He's never done anything like the crime of separatism they accuse him of," she told Reuters Television. "And I'm under so much pressure ... I'm not particularly free leaving my own home - wherever I go (police) are always trailing me."
Li said he believed his client was "an extremely open and transparent person. All that he has done is in his interviews, in class lectures and in his online content."
The charge is the latest sign of the government's hardening stance on dissent in Xinjiang, gripped by periodic outbursts of violence often pitting Uighurs against ethnic Han Chinese.
Many Uighurs chafe at restrictions on their culture and religion, although the government says it grants them broad freedoms. China blames some of the violence on Islamists who want to establish an independent state called East Turkestan.
But rights groups and exiles say China exaggerates the threat to justify its firm grip on energy-rich Xinjiang, which borders ex-Soviet Central Asia, Afghanistan, Pakistan and India.
CHALLENGING THE GOVERNMENT'S VERSION
Advocates for Tohti say he has challenged the government's version of several incidents involving Uighurs. That includes what China says was its first major suicide attack, in Beijing's Tiananmen Square in October, involving militants from Xinjiang, by pointing out inconsistencies in the official accounts.
"China's accusation of so-called separatism is a political excuse to suppress Uighurs who express differing opinions," Dilxat Raxit, a spokesman for the main Uighur exile group, the World Uyghur Congress, said in an emailed statement.
In Washington, U.S. State Department spokeswoman Jen Psaki called for Tohti's release.
"We are deeply concerned by reports that Chinese authorities have decided to formally arrest economics professor Ilham Tohti after detaining him for more than a month without access to his family or attorney," Psaki told reporters at her daily briefing.
"We call on Chinese authorities to release Mr. Tohti and to guarantee him the protections and freedoms to which he is entitled under China's international human rights commitments, including the freedom of expression," she added.
Tohti, who teaches at Beijing's Minzu University which specialises in ethnic minority studies, told Reuters in November that state security agents had threatened him for speaking to foreign reporters.
"I have never associated myself with a terrorist organisation or a foreign-based group," Tohti told Radio Free Asia's Uyghur Service last year in a statement he asked to have released if he was taken into custody.
"I have relied only on pen and paper to diplomatically request the human rights, legal rights, and autonomous regional rights for the Uyghurs."
The foreign ministry, the only government department which regularly answers questions from the foreign media, declined to comment directly on the case.
"I believe that China is a country with rule of law and judicial authorities will try the case in a fair and legal way," spokeswoman Hua Chunying told a press briefing on Wednesday. (Additional reporting by Ben Blanchard and Joseph Campbell; Editing by Ron Popeski)