"These prices are unheard of! They are worse than the Ramadan heat wave," says Aisha, cradle in hand, sheltering from the blazing sun in Tunis' central market during the Muslim fasting month.

It is Tunisia's first Ramadan under an Islamist government, which promised to rein in food prices when it came to power seven months ago but has yet to do so, and poor Tunisians are struggling to cope.

"This year everything is expensive; the prices have hit all-time highs," complains the housewife, as she eyes the well-stocked shelves, whose contents remain largely out of her price range.

"People can only look and go on their way," says Aisha, adding that for iftar, the evening meal when Muslims break their fast, she is forced to feed her family a plate of kadhab, any sort of vegetarian poor-man's dish without protein.

Amid the cries of market traders and the pungent smell of fish, disadvantaged Tunisians wander round the stalls searching for affordable food.

"One kilo of lemons today, at four dinars (two euros/$2.46), is eight times more expensive than before Ramadan! It's a disgrace," says Souha, blaming the speculators who profit from the hunger that follows the day-long fast.

"Briks without lemon during Ramadan, there's no point!" she adds, referring to a Tunisian dessert widely-eaten during Ramadan.

Selima, a textile worker, says: "With my budget of 160 dinars (90 euros) I could get by for the month, but this year I've spent it all in the first week."

At the end of April, Prime Minister Hamadi Jabali pledged to bring down the cost of consumer goods before Ramadan, but it was a promise that rang hollow as prices continued to climb.

What is supposed to be a period of abstinence for Muslims, the holy month often paradoxically leads to a frenzy of consumer demand and price hikes.

In a bid to curb price speculation, the authorities deployed monitors, but they have met with hostility from some traders. Even so, more than a thousand offenses were recorded in the first five days of Ramadan.

"The government must do what is necessary to contain high prices and increase salaries, otherwise it will be punished in the next elections," says Mohammed, a civil servant.

"What is more important than allowing people to eat during Ramadan?" he asks, recalling that last year's revolution, which ousted dictator Zine El Abidine Ben Ali, was sparked by frustration at the poverty and precarious livelihoods of so many Tunisians.

"People sacrificed their lives. We have a government and elected MPs, but the prices have not fallen one iota," says his wife Nabila, who works in a bank.

The coalition government, formed after the first post-uprising poll in October, has raised the minimum monthly salary to around 150 euros, and talks over public and private sector pay increases are in their early stages.

But for now, the cost of living is frequently satirised in the media, with newspapers devoting entire sections to the problem of high food prices and sometimes offering cheap recipes to help people make ends meet.

"You have to secure a bank loan to make chakchouka" these days, quipped one radio commentator recently, referring to a highly popular, spicy dish made of tomatoes, onions, eggs and peppers.

Tunisia went into recession last year, and despite recovering in 2012, the economy remains fragile. Unemployment, which spurred many of the revolutionaries into action, hovers at around 19 percent.

The Ben Ali regime repeatedly claimed that less than four percent of the country's population lived in poverty, but after the revolution it emerged that this was a gross underestimate, the real figure estimated at almost a quarter.