The authorities in Georgia have threatened to issue an arrest warrant for ex-President Mikheil Saakashvili if he fails to return for questioning.
The pro-Western politician left Georgia after his term as president ended in November, when an opposition candidate was elected to replace him.
Prosecutors want to question him about the suspicious death of ex-Prime Minister Zurab Zvania and other cases.
He argues he is the victim of a witch hunt orchestrated by Moscow.
Prosecutors said they expected Mr Saakashvili to appear for questioning on Thursday but reports suggest he will refuse to return.
The US state department and the EU have both criticised the Georgian government for seeking to prosecute former officials.
Dozens of them are under investigation or have been charged. In some cases, they have been jailed for offences committed in office.
Mr Saakashvili is known in the West as a charismatic leader who eliminated petty corruption, tackled bureaucracy and challenged Russia in a brief war in 2008, the BBC's Rayhan Demytrie reports from the Georgian capital, Tbilisi.
But domestically many accuse the former leader of being authoritarian and for allowing high-level corruption to flourish, our correspondent adds.
Mr Saakashvili has taken up a post lecturing at Boston's Tufts University. He has been seen at various events in Europe this month, sharply criticising Russia's annexation of Crimea.
Speaking on Tuesday from an undisclosed location to a private Georgian TV channel, Mr Saakashvili said he had left Georgia last year on the advice of Western officials because of the risk of arrest there.
"One of the heads of the US state department - not one, but several - and John Kerry also raised this issue during his conversation with me when I was on an official visit in Washington," he told Rustavi-2 TV.
The former leader accused Georgian Prime Minister Irakli Gharibashvili of going against legal procedures by threatening to have him placed on an international wanted list if he failed to come in for questioning as a witness.
He also accused his chief political foe in Georgia, businessman Bidzina Ivanishvili, of threatening two years ago to have him prosecuted if he did not "shut [his] mouth".
A Saakashvili ally, former Prime Minister Vano Merabeshvili, was sentenced last month to nine years in prison as a result of two separate trials for abuse of power.
Zurab Zvania, a key figure along with Mr Saakashvili in Georgia's 2003 Rose Revolution, was found dead at the home of a friend on 3 February 2005, the apparent victim of gas poisoning.
Investigators have reportedly uncovered evidence of unexplained injuries to his body.