Beirut, Lebanon (CNN) -- Saad Hariri said Thursday he is ready to stand again as prime minister of Lebanon despite objections from the militant Shiite group Hezbollah.
In a televised speech to the nation, Hariri invoked the name of his late father and said he and his party had sacrificed to build the country socially and economically. He said he would not relinquish Lebanon's gains over political infighting.
"I worked hard to protect Lebanon from unrest," he said just hours after Turkey and Qatar suspended efforts to broker a new government in Lebanon. Saudi Arabia threw in the towel a day earlier, according to regional news agencies.
Lebanon's unity government collapsed last week when ministers loyal to Hezbollah quit their posts.
The dispute centered on a U.N.-backed tribunal's investigation into the 2005 assassination of Hariri's father, former Prime Minister Rafik Hariri. The tribunal is widely expected to blame Hezbollah for the killing.
Lebanese President Michel Suleiman asked Hariri to stay on as caretaker prime minister.
"This is a historic crisis that has touched all Lebanese," Hariri said Thursday. "We must resort to the constitution and constitutional organizations. This should be the basis on which everybody works."
The leaders of Turkey, Syria and Qatar met personally earlier in the week to approve the Turkey-Qatar mission to try to resolve the political crisis and the Turkish and Qatari foreign ministers were in Beirut this week for talks with Lebanese leaders.
"Due to some reservations they decided to stop their efforts in Lebanon at this time and leave Beirut for more consultations with their leaderships," according to a statement reported by Lebanese and Qatari news agencies.
"The United States supports the independence and sovereignty of Lebanon and believes that, ultimately, any decision will have to be made by the Lebanese people," U.S. Secretary of State Hillary Clinton said Thursday. "Any mediation effort engaged in by anyone outside of Lebanon itself should be aimed at supporting the people of Lebanon and making decisions that will lead to stability and security, justice, and a commitment to bringing those who committed the murders of Prime Minister Hariri and 22 others to account."
"I think that over the next days you'll see a lot of activity within Lebanon itself, and we stand ready, as do many others in the region and beyond, to be of assistance," Clinton said. "We strongly support the ongoing work of the tribunal and believe that it is in the long-term interest of Lebanon to end impunity for political killing."
Some Lebanese networks reported Thursday that Suleiman might be heading to Syria soon for talks with his Syrian counterpart, but the presidential palace in Beirut would not confirm the report.
Iranian President Mahmoud Ahmadinejad spoke to Turkish Prime Minister Recep Tayyip Erdogan about the crisis by phone on Wednesday, Iran's official IRNA news agency reported. It was their second talk about Lebanon this week.
Prince Saud al-Faisal, Saudi Arabia's minister of foreign affairs, said Wednesday that his country had abandoned mediation talks to resolve the crisis, despite the situation being "dangerous."
Saudi Arabia's King Abdullah and Syrian President Bashar Al-Assad have been personally involved in an attempt to resolve Lebanon's political crisis, the Saudi foreign minister said. But when no agreement was near, the Saudi king "lifted his hands and kept away from the negotiations," al-Faisal said.
Hariri was in Washington meeting with U.S. President Barack Obama when his government collapsed a week ago. On his way back to Beirut, he stopped in Ankara for talks with the Turks.
CNN's Elise Labott, Nada Husseini and Amir Ahmed contributed to this report.