The ED today also examined the state-owned bank's Executive Director KV Brahmaji Rao to understand how the alleged fraud was detected and other banking procedures.
Mehta, officials said, will be asked similar questions when he meets ED officials this week. They said the two officials are not being examined as accused.
The CBI had examined the two senior PNB officials last week in the same case.
Meanwhile, diamond merchant Modi, his wife Ami and uncle Choksi today skipped their scheduled appearance before the Enforcement Directorate (ED) in Mumbai.
It was not immediately known if the agency will issue fresh dates to them.
If it does not issue them fresh summons, it is understood, the ED is expected to move a special court in Mumbai seeking non-bailable arrest warrants against them.
The agency today also obtained the court's nod to issue six Letters Rogatories (LRs), judicial requests for obtaining information from overseas locations, pertaining to its probe against Modi.
The agency is expected to obtain more such LRs in this case.
The attempt of sending these judicial requests for exchange of information is aimed at obtaining the details of the overseas financial holdings of Modi and Choksi and also their bank accounts, assets, partnerships, showrooms, trusts and other assets, the officials said.
These assets and their sources of income will be investigated and if necessary would be attached under the criminal sections of the Prevention of Money Laundering Act (PMLA) if it is found that they have been created using tainted funds or the proceeds of crime of the alleged bank fraud, the sources had said.
The total assets seized by the ED in this case is now over Rs 6,393 crore, officials had said, adding that this was being independently valued.
Modi, Choksi and others are being investigated by the ED and other probe agencies after the fraud recently came to light, following a complaint by the PNB that they allegedly cheated the nationalised bank to the tune of Rs 11,400 crore, with the purported involvement of a few employees of the bank.
The CBI and the ED have registered two First Information Reports or FIRs each to probe the case. Both Modi and Choski are said to have left the country before criminal cases were lodged against them.
The ED, a central probe agency under the Union finance ministry, is investigating if the allegedly defrauded bank funds were laundered and proceeds of crime were subsequently used by the accused to create illegal assets and black money.