Arrested by the Punjab police in the drugs case in 2013, Mr Chahal, who owns a pharma company, is currently out on bail. His statement is part of the charge-sheet filed in a Patiala court on March 3 by the Enforcement Directorate.
The agency is probing the money laundering angle in the case.
Ahead of the budget session in Punjab assembly, the allegations have created a storm with the opposition demanding Mr Majithia's ouster.
"This is serious allegation, the ED should look into this. We demand that Majithia step down as minister," said Sunil Jahkar, leader of the opposition in Punjab assembly.
Aam Aadmi Party MP from Punjab Bhagwant Maan demanded that a case be registered against Mr Majithia and the trial be conducted outside the state.
But sources close to Mr Majithia have strongly refuted the allegations saying it's a ploy to malign his reputation adding that it's not the first time such allegations have been made, curiously just a few days before the Punjab assembly session is set to begin.
The younger brother of Union minister Harsimrat Kaur Badal, wife of Punjab Deputy Chief Minister Sukhbir Singh Badal, Mr Majithia faces allegations of having links with non-resident Indians accused of international money laundering related to the drugs racket.
His name had surfaced in the case after Jagdish Bhola, a man arrested last year for drugs trade, alleged in court that it was being run under the minister's patronage and the full knowledge of the state police.He was questioned by the Enforcement Directorate in December.