The home of the ex-head of Greece's bank rescue fund has been raided in a tax evasion probe
The Athens raid happened on July 4, said the FT report, citing people familiar with the situation. Sclavounis has not yet made a public statement about the alleged raid.
Sclavounis was the head of UBS's investment banking arm in Greece, which he set up in 1997, before being appointed chairman of the Hellenic Financial Stability Fund in 2013.
He stepped down in 2015, a month after Syriza came to power in Greece.
The fund received about €48 billion (£40.1 billion, $53.1 billion) between 2012 and 2014 as part of bailout agreements to rescue Greek lenders. Just over €37 billion was used, leaving a buffer of €11 billion.
Swiss banks are under pressure from other global governments to co-operate with tax evasion investigations. On Sunday, UBS Chief Executive Sergio Ermotti, warned of an "offensive" against Swiss banks.
He said in an interview that Switzerland's politicians have done too little to protect the country's lenders from data demands from foreign governments.
"This is unacceptable and opens the door for a new offensive against Swiss banks," he said, according to a Reuters report. "On some issues, the train has left the station," he said.
Authorities in France, Germany and the United States have started tax probes into Swiss banks since the 2008 financial crisis.