Jeff Skilling, the former Enron boss facing multiple fraud charges over the collapse of the company, has strongly denied he ever entered into any pact or agreement with Andrew Fastow, the disgraced ex-finance chief.

Fastow, who was jailed for 10 years for his role in covering up the massive fraud at the company, had earlier testified that Skilling made a secret deal with him that would protect him from losing money on side deals he made with Enron.

Fastow said he had a 'bear hug' agreement with Skilling that Enron would make sure the LJM partnerships – set up to hide massive losses at the company - did not lose money.

Testifying for the second day running, Skilling denied any such agreement with Fastow and also went on the offensive attacking several other government witnesses that linked him to illicit dealings at the company, Reuters reported.

Skilling, 52, and former Enron CEO and chairman Kenneth Lay, 63, are charged with lying to analysts and investors. Both deny any wrongdoing.