Islamist groups and members of Sudan's ruling party have called on President Omar Hassan al-Bashir to cancel deeply unpopular austerity measures amid deadly unrest.
The call on Saturday came after police fired teargas to break up thousands of people in the capital during a sixth day of protests against cuts to subsidies on cooking oil and fuel that doubled pump prices over Friday night.
The government has not allowed citizens to demonstrate peacefully
Several people were injured in Sudan's capital Khartoum after police opened fire on a funeral that turned into an anti-government protest.
Thirty-one members of the quasi-official Islamist Movement and the ruling National Congress Party (NCP) signed the petition, the first sign of dissent inside ruling circles after a week of unrest that has killed dozens.
"Mr President, in the light what is happening we demand an immediate stop of the economic measures," the petition read.
Demonstrators called Bashir a "killer" at the funeral on Saturday - the sixth day of protests spurred by udprice increase in the northeast African country already burdened by economic pain and war.
Tear gas was fired on thousands of people who had gathered for the funeral of Salah al-Sanhouri, a 26-year-old pharmacist who was killed the previous day, chanting: "The people want the downfall of Bashir."
Thousands of people have been out on the streets daily across Sudan, angry at the rising cost of fuel. Authorities say 33 people have died over the past week.
More than 1,000 people had gathered in Khartoum's Burri district, home to a senior government official, for Saturday's funeral, before it grew to more than 3,000, witnesses said.
Sudan's information minister told Al Jazeera the government had expected anger after it withdrew the fuel subsidy, but that the protests had turned into "riots".
Hajooj Kuka, a Sudanese youth activist, told Al Jazeera on Saturday that the situation in Sudan was "like a war zone".
Human-rights groups have accused the government of violent repression of protesters by adopting a shoot-to-kill policy.
Al Jazeera's Harriet Martin, reporting from Khartoum, said it was "impossible to verify how many people have been killed", and that while the government has put the figure at 33, medical sources say it could be as high as 200.
She said it was unclear whether the government's use of of force would "keep the people from taking to the streets, or ... give them more reason to do so".
It is highly unusual for members of the political elite to question his actions publicly.
The petition called for the prosecution for those responsible for opening fire on protesters and compensation for relatives of killed people.
"The government has not allowed citizens to demonstrate peacefully," the petition read.
There was no immediate reaction to the petition from the government, which has not acknowledged using live ammunition.
The petition was signed by former NCP parliamentary caucus head Ghazi Salah el-Din and a prominent army officer who authorities accused of being involved in a coup attempt against Bashir last year.
Bashir has ruled Sudan since coming to power in a bloodless 1989 coup. He has not commented on the protests since announcing the lifting of subsidies on Sunday - part of austerity measures driven by a severe financial crunch exacerbated by the secession of oil-producing South Sudan in 2011.