Houthi Shiite rebels and their supporters release fireworks after Shiite rebels announced that they have taken over the country and dissolved parliament in Sanaa, Yemen, Friday. (Hani Mohammed/AP)

Shiite insurgents moved to consolidate full control over Yemen’s leadership Friday, announcing the disbanding of parliament and plans to form a transitional authority to run the conflict-racked country that hosts a powerful al-Qaeda affiliate.

The sweeping moves follow an offensive by the Houthi rebels last month that forced the resignation of President Abed Rabbo Mansour Hadi and his government, which had been a key ally in U.S. drone strikes against the Yemen-based al-Qaeda in the Arabian Peninsula (AQAP).

The rebels’ televised statement casts further uncertainty over the country’s cooperation with Washington in counterterrorism operations, including the drone program, which is highly unpopular among Yemenis but has continued during the latest unrest.

The White House said Friday it was “deeply concerned” by the rebel announcement, claiming the moves violate U.N.-drafted protocols seeking to stabilize the country.

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The Houthis oppose al-Qaeda as a rival faction, but they also denounce the U.S. drone strikes as a violation of Yemen’s sovereignty.

The rebels — who follow the Zaydi offshoot of Shiite Islam — have clashed with AQAP after storming into the capital, Sanaa, in September and gradually pushing south. On Thursday, AQAP announced that one of its top leaders, Harith al-Nadhari, died in a drone strike last month.

Al-Qaeda’s Yemen branch is considered one of the most active cells of the terror network and has claimed a role in several high-profile attacks or plots. Last month, the group claimed that it helped to fund and plan an attack in Paris on the satirical newspaper Charlie Hebdo.

Further steps by the rebels to consolidate power also are likely to sound alarm bells in neighboring Arab countries, especially in Saudi Arabia, that view the Houthis as proxies for Shiite-led Iran, a charge the Houthis deny, arguing that they are a strictly Yemeni movement.

In Washington, Rep. Edward R. Royce (R-Calif.), chairman of the House Foreign Affairs Committee, said Iran is playing an “increasingly destructive role” in the region, and he urged the Obama administration to “come to grips” with it. “This takeover of Yemen by the Iranian-supported Houthi militia is a very dangerous blow to our national security,” he said in a statement. “Iran is consolidating its grip on the region, our embassy is on lockdown, and al-Qaeda has more room to operate.”

State Department spokeswoman Marie Harf said Friday that the United States still recognizes Hadi as the president of Yemen and that “when it comes to counterterrorism, we are continuing to work with the Yemeni security forces.”

Last month, the Houthis trapped Yemen’s president and other government officials in their homes.

In their televised address, the rebels announced the dissolution of parliament and its replacement by a soon-to-be-named 551-member transitional council that would run the country for two years.

That council would elect a five-member presidential body and pave the way for future parliamentary and presidential elections, the rebels said.

Some immediately rejected the Houthi announcement, signaling further discord in the Arab world’s most impoverished nation.

“This announcement is baseless and represents only one side. It does not speak for Yemen, and it is not legislative; nor is it legal,” said Ahmed Mohammed Othman, a prominent political figure in the city of Taiz, where anti-Houthi sentiment has been rising.

The process of forming the transitional authority appears to be entirely overseen by the Houthi rebels.

The group’s self-declared revolutionary committee would select members of the transitional council. That committee, which is the intelligence arm of the Houthi movement, is run by a family member of the group’s leader, Abdulmalek al-Houthi.

Mohammed Albukhaiti, a member of the Houthi politburo, called the group’s decision “a clear message to the international community not to interfere in Yemen’s internal affairs, and I believe that it’s our sovereign right.”

Speaking by telephone, he cited unspecified groups that were threatening Yemen with “chaos.” Because of that threat, the rebels were forced to dissolve parliament and form a transitional government, he said.

Friday’s announcement was delivered at the presidential palace in Sanaa and appeared to be accepted by apparent rivals, including the former defense and interior ministers, who were in attendance.

The Houthis had set Wednesday as the deadline for negotiations held by a number of political factions to form a transitional government, but that collaborative effort appears to have been overruled by the rebel group.

Naylor reported from Beirut.