Up to 5,000 people protested in the Moroccan capital Sunday against the Islamist government and the high cost of living after price rises of staple goods, an AFP journalist said.
The peaceful demonstration came as local press also reported a threatened 72-hour general strike in the transport sector from Monday.
Sunday's demonstration took place after a call by the UGTM trade union which is close to the nationalist Istiqlal party.
Istiqlal in May announced its intention to quit the coalition headed by the Justice and Development Party of Prime Minister Abdelilah Benkirane.
Some protesters brandished placards bearing a "thumbs down" symbol.
"We're protesting because of high prices of milk, meat and now petrol," 48-year-old Hassan Marrakchi told AFP.
"And there's no work. We don't want Benkirane -- he's done nothing."
Press reports said Istiqlal chief Hamid Chabat, who is also the mayor of Fez, hired hundreds of buses to ferry demonstrators to the capital for the protest.
Petrol prices jumped on Monday as the cash-strapped government began implementing a fuel price indexation system aimed at reining in oil subsidies and plugging a budget deficit.
The government is scrambling to limit the impact of oil price fluctuations on Morocco's ailing public finances, with fuel subsidies weighing heavily on the budget of the North African country, which imports almost all its energy needs.
Under the controversial indexation system, the price of diesel surged 8.4 percent to 0.79 euros per litre, while petrol hit 1.14 euros a litre, a rise of 4.8 percent, a government official confirmed to AFP.
The move increased the pressure on many ordinary Moroccans already struggling to make a living.