Directors of collapsed construction giant Carillion have been accused of being "contemptuous" of their pension obligations.
The chairman of a select committee said letters he had received since a Parliamentary inquiry was launched suggested they "refused to give an inch" to the company's pension schemes.
Frank Field, who chairs the Work and Pensions Committee, said he hoped the Pension Regulator was now "going after" some of the "very generous" bonuses paid to directors.
In one letter in 2013, the trustee of five Carillion schemes tells the Pension Regulator that the December 2011 actuarial valuations and associated documentation could not be signed off by the statutory deadline of March 2013.
The trustee said an "impasse" had been reached and called for a formal intervention by the regulator.
Mr Field said: "These letters suggest the Carillion directors were contemptuous of their pensions obligations.
"Over two successive 15-month negotiations they refused to give an inch to the pension schemes.
"Their private pleading that the company could not afford more was in stark contrast to the rosy picture - and bumper dividends - being presented to the outside world.
"Richard Adam, the longstanding finance director, has particular questions to answer.
"With characteristic alacrity, the Pensions Regulator started its arduous process of chasing money down from Carillion a few days after it was formally announced there was no money left.
"I can only assume - and hope - they are going after some of those very generous bonuses."
The pensions regulator opened an investigation into Carillion on January 18, three days after it went into insolvency.
The number of Carillion workers who have lost their jobs has topped 1,000.