While Davis admitted the UK would continue to contribute about £10bn a year to the coffers of Brussels until early 2019, nothing had been finalised about the final payment.
It was suggested last week ahead of Theresa May’s key speech in Florence that she would be announcing a €20bn transition deal to the EU to smooth the way for formal trade talks to begin.
However, while the prime minister proposed a two-year ‘extension’ to the UK’s relationship with the European Union, no figure was mentioned.
Davis insisted that there were plenty of areas such as pension contributions that were open to be challenged during the negotiations.
He told BBC1’s Andrew Marr Show: “The last time we went through line by line and challenged quite a lot of the legal basis of these things and we’ll continue to do that.
“That doesn’t mean that we want to see our allies and friends in Europe massively disadvantaged in the next few years and that’s what we’re aiming not to do.”
And as for the reported £40bn final settlement as the UK leaves, he added: “They sort of made that up too.
“I’m not going to do an actual number on air, it would be ridiculous to do that, but we have a fairly clear idea where we’re going on this.”
Davis and Michel Barnier, the man leading the EU side of the talks, have been butting heads for months on the thorny issue of the divorce bill – plus the future of the Irish border and citizens’ rights.
Barnier has insisted that no trade talks can begin until those three areas are addressed.
May’s Florence speech was an attempt to move the debate along, raising the prospect of the UK remaining committed members of the EU in all but name until 2021.
The prime minister sought to reassure member states that they would not lose out financially during the current EU budget period, which runs to 2020.
She also confirmed there would be no restrictions on EU citizens coming to the UK during the transition period, but after Brexit they would be registered as they arrived.
Whether that will be enough to see some real progress made this week in the latest round of talks between Davis and Barnier remains to be seen.
Barnier is sure to ask – again – just how much Britain is willing to pay as it leaves the bloc.
EU leaders are due to meet in October to discuss the separation issues and whether enough progress and reassurances have been given in order to allow bilateral trade talks to start.