Girma Seifu Maru has possibly the loneliest job in African politics. Five hundred and forty-six members of the Ethiopian parliament are loyal to the ruling party. He alone is not.

But the country’s sole opposition MP has warned that unless the government opens up to critical voices and guarantees human rights, it faces a potentially “violent struggle”.

In a rare interview with the Reuters news agency in Addis Ababa, Girma argued that Ethiopia’s impressive economic growth of 10.6% over the past decade was based on Chinese-style authoritarianism and must go hand in hand with political freedoms.

“The Chinese model is that economic development is the primary issue; don’t ask about human rights issues, don’t ask about your freedom, keeping silent on people’s rights so that a few politicians get the economic benefits,” said the 47-year-old economist.

The government risked a popular backlash if it did not change direction, he said. “That will be a seed they are just giving water to at this time if they don’t change their route and give hope to peaceful activities.”

To the outside world, a construction boom in Addis Ababa appears to symbolise how far the country has come since the infamous famine of the 1980s. But frustration at autocratic rule is intensifying. In June, witnesses said, thousands of Ethiopians staged the country’s biggest anti-government demonstration since 2005.

Last month Amnesty International warned that basic rights were under attack after two opposition parties reported the arrests of many members attempting to hold peaceful protests.

Hopes of change via the ballot box seem remote. The disputed 2005 election ended in violence and the deaths of 200 people. Opposition candidates won 174 seats but many did not take them up, alleging that the vote was rigged.

Girma was the only opponent to win a seat in 2010. He claims that the ruling Ethiopian People’s Revolutionary Democratic Front (EPRDF) and its allies used state institutions to keep out most rivals.

The Reuters interview noted: “Dressed in a tracksuit and sipping a local St George beer, he brushed off with a smile the idea he was lonely in parliament. ‘I am one and they are one,’ he said.”

The next parliamentary elections will be held 2015. Girma says his party, Unity for Democracy and Justice (UDJ), is committed to reform by peaceful means and pushing for greater openness with a “millions of voices for change” campaign and demonstrations for freedom around the country.

Girma said his party activists had also launched a petition to repeal the 2009 anti-terrorism law, which rights groups say has been used to lock up opponents. Human Rights Watch says 13 journalists have been convicted since 2011, including Eskinder Nega Fenta, a journalist and blogger who received the 2012 PEN Freedom to Write award.

“A spirit of fear is very dangerous,” Girma said. “So if individuals can become free of this fear, they can bring change.”

Amnesty said last month: “As eyes begin to turn towards the parliamentary elections due to be held in 2015, the Ethiopian government must release its stranglehold on political participation. The authorities must allow political opposition parties to function without harassment, and allow all persons, including peaceful protest groups, to exercise their rights to freedom of expression, assembly and association.”

But the government brushes off such criticism. Hailemariam Desalegn, who became prime minister following the death of Meles Zenawi in 2012, said last week that it could not be blamed for the opposition’s weak showing. “Shall we say to the people: elect this guy or that guy?” he asked Reuters. “It is the people who decide.”