“I think the first thing to say is Ecuador has been making some pretty outrageous allegations over the past few days to justify what was an unlawful and extraordinary act in allowing British police to come inside an embassy,” she said.
Pressed over the veracity of the allegations, Ms Robinson said: “That’s not true.”
She also said Assange’s fears of a US extradition threat were proved correct this week after allegations were made that he conspired to hack into a classified Pentagon computer.
Assange faces up to 12 months in prison after being found guilty of breaching his bail conditions when he entered the Ecuadorian embassy in 2012.
He made the move after losing his battle against extradition to Sweden where he faced allegations including rape.
Assange is now expected to fight extradition to the US over an allegation that he conspired with former army intelligence analyst Chelsea Manning to break into a classified government computer.
Labour leader Jeremy Corbyn has joined Assange’s supporters in saying he should be protected against extradition to the US because he exposed evidence of “atrocities” in Iraq and Afghanistan.
More than 70 MPs have also urged the Government to ensure Assange faces Swedish authorities if they request his extradition.