The treaty needs to be ratified by various authorities in India as also in Switzerland, including the Parliament of the European nation, and it might come into force by the end of 2011 depending on these approvals, a spokesperson for the Switzerland's Federal Department of Finance told PTI.
If all these ratifications are achieved by 2011-end, the provisions of the treaty, which includes information exchange about suspected tax evaders and other financial offenders, would come into effect in India from the fiscal year beginning on or after first day of April 2012, the official said.
This means that India would be able to seek information on tax evasion and other financial offenses on incomes for the fiscal year 2012-13 beginning April 1, 2012, onwards and not for the past periods, experts said here.
Still, it is unlikely that the names of Indians having money in Swiss banks would be made public, as being demanded by the opposition parties, because such a step would not only be in breach of the bilateral treaty, but could also hinder the process of investigations, they added.
In Switzerland, the provisions would come into effect for fiscal year beginning on or after January 1 of the year following the one when treaty comes into force, the Swiss Finance Department official said.
Indian government is facing intense pressure from the opposition parties, as also the Supreme Court, on issue of black money allegedly stashed away by some Indians in Swiss banks and other tax havens.
The issue of Indians having secret Swiss bank accounts has become a political hot potato, amid reports of Indians having billions of dollars in banks in Switzerland. But, there are no official figures as such and experts believe that it was not necessary that all the funds deposited by Indians in Swiss banks were black money.
Finance Minister Pranab Mukherjee and Swiss Federal Councillor Micheline Calmy-Rey signed a "protocol" on August 30, 2010 to amend the double taxation agreement (DTA) in the area of taxes on income.
The revised tax treaty was expected to facilitate the Indian government seeking details about illicit wealth allegedly stashed away by Indians in Swiss banks.
However, this Protocol has not entered into force yet and needs to be ratified by the authorities in two countries.
Asked about the status, the Swiss Federal Department of Finance official said that one of the parliament commissions in charge of the DTAs last week decided to approve the DTA with India and the parliamentarial approval process was expected to come to an end by September 2011.