Bakiyev fled to the Jalalabad region of the mountainous Central Asian state from the capital Bishek after troops fired on protesters on April 7, sparking the uprising that brought his opponents to power.

Bakiyev, who swept to power five years ago in the "Tulip Revolution" that ousted the country's first post-Soviet ruler Askar Akayev, warned the self-proclaimed interim government that any attempt to detain him would result in bloodshed.

"We have abolished his presidential immunity... We expect him to show up voluntarily (to resign formally). But he continues rallying with his supporters in Jalalabad," said Azimbek Beknazarov, the interim minister in charge of security.

At least 82 people died and hundreds more were wounded in the firing on April 7.

Bakiyev has been mustering supporters in the south and has brushed aside demands from the interim government to resign or leave the country and led a rally in the city of Jalalabad on Tuesday.

Around 3,000 supporters gathered, waving banners and shouting "Down with the bloody interim government." There were no signs of heavy security, with Bakiyev guarded only by a handful of security personnel dressed in dark sportswear and armed with AK-47 rifles. Bakiyev was due to deliver a speech at the rally.

The new security minister said he should surrender after addressing his supporters.

"We have opened a criminal case against the former president. If he does not show up today after the rally we will hold an operation to detain him," Beknazarov said.

The drama of the standoff in Kyrgyzstan, an impoverished nation of 5.3 million people, is important to the United States because of the Manas air base which it rents to support the war in Afghanistan.

The United States says the interim government has pledged to abide by its agreements on Manas, the last remaining US military base in Central Asia after Uzbekistan evicted the United States from a base in 2005.

US Assistant Secretary of State Robert Blake will visit Bishkek this week to meet with the interim government, the highest level US visit since Bakiyev fled the capital.

Blake said there were no plans to meet with Bakiyev and stressed the dispute must be resolved constitutionally.

He added that the United States was not yet formally recognising the self-proclaimed government.

But a US military official said in Washington that Manas would not be used as a hub for sending troops into Afghanistan in the near term, citing the need to free it up for possible humanitarian aid or other logistical purposes.

In his first public appearance since troops fired on protesters during the rebellion, Bakiyev told thousands of supporters on Monday that any attempt to kill him would result in bloodshed.

"I believe this will lead to such a great deal of bloodshed which no one will be able to justify," he said. "Let them try to seize me. Let them try to kill me."