East Timor's President Xanana Gusmao said the unrest plaguing his country had "shaken" the nation's leaders.
This was Mr Gusmao's first address since the violence began
"We have witnessed the state become paralysed," he admitted in his first address to parliament since violence broke out last month.
Mr Gusmao also vowed to uphold the country's constitution.
He was speaking after Kofi Annan said he believed UN peacekeeping forces would have to return to East Timor, just a year after they were withdrawn.
The unrest was sparked by the sacking of 600 soldiers who had gone on strike claiming discrimination.
Many people blame the prime minister, Mari Alkatiri, for not preventing the recent clashes - in which at least 20 people have died.
Mr Gusmao admitted in his televised address on Wednesday that the crisis had reminded the nation's leaders "that something was wrong".
"We have witnessed the state become paralysed in the wake of all the events that took place in Dili, and worse than that, we have witnessed that the population is suffering from the consequences," he said.
Mr Gusmao added that the fact his country needed to ask for international intervention should "frighten all of us who were elected by this people to ensure stability, security and better living conditions."
He said he would "continue to fulfil the sacred duty of safeguarding the democratic state" as a "guardian of the constitution".
Mr Gusmao did not comment directly on whether he supported the move by Mr Alkatiri's opponents to oust the PM, but his speech suggested he would not go along with their plans.
Kofi Annan told a meeting of the Security Council in New York on Tuesday that he was "deeply concerned" about the situation in East Timor.
"It is obvious that the UN will have to go back in a much larger form than we are at the moment," he said. "And we will need to send an assessment mission on the ground to determine exactly what needs to be done."
International peacekeepers led by Australia are now patrolling the capital, and Mr Annan said it could take months before a possible handover to the UN.
According to a BBC correspondent in New York, East Timor was heralded as a great success for the UN - a model of nation building.
But Mr Annan admitted that the Security Council had scaled down the previous UN mission too quickly.
"The sad events of recent weeks reflect shortcomings not only on the part of the Timorese leadership but also on the part of the international community in inadequately sustaining Timor-Leste's (East Timor's) nation-building process," he said.
In East Timor, the UN's special representative Sukehiro Hasegawa said international prosecutors had arrived in Dili and would be working with the prosecutor-general's office to investigate the violence.
"They have commenced their criminal investigations into the incidents and events that took place in April and May, and they will continue to do so with a view to finding what
really happened," he said.