Yemen’s Shiite rebels faced mounting pressures and signs of internal divisions Friday after the U.S.-backed president and his cabinet resigned rather than submit at gunpoint to their increasing demands for power.

With thousands of demonstrators on both sides taking to the streets across the impoverished Arab country, the rebels appeared wary of the dangers of overstepping in Yemen’s minefield of tribal politics, sectarian divisions, al-Qaida militancy and a strong secessionist movement.

Although rebel gunmen manned checkpoints throughout the capital and continued besieging the houses of government ministers, they made no public attempt to fill the vacuum created by the resignations of President Abed Rabbo Hadi, his prime minister and cabinet. And there were signs that the national parliament would reject the resignations when it meets Sunday.

Indeed, it seemed as though the rebels, known as the Houthis, do not want to rule the country outright and would prefer that Hadi remain as a figurehead president.

In his latest speech, rebel leader Abdel-Malek al-Houthi vowed to keep up the pressure until the government meets all his demands, including greater representation in government ministries and in a committee to rewrite the country’s constitution. He stressed his group’s opposition to dividing the country — a measure in the draft constitution that would diminish the resources under the Houthis’ control.

Yemeni law dictates that the parliament speaker - Yahia al-Rai, a close ally of former autocratic ruler Ali Abdullah Saleh — will now assume the presidency. Saleh, who stepped down in 2012 a year after widespread street protests, still wields considerable power and is believed to be allied with the Houthis.

“The strong majority of people are against Houthis’ expansionist move,” said political analyst Omar Abdel-Aziz. “Pressure from different regions on them right now are mounting.”

The Houthis were also confronted with dissent from within their own ranks. Ali al-Bukhaiti, a prominent member of the group’s political arm, resigned Friday.

In a statement posted on his Facebook page, al-Bukhaiti said the Houthis had become “the official authority” in the country. He said he wanted to work as a mediator to “lessen the political polarization which is transforming into a regional and sectarian polarization that threatens the whole nation with fragmentation.”