A Government minister has suggested Priti Patel accepted an invite to a Bond premiere in her capacity as Home Secretary because it had links to her department.

Michael Ellis, the Minister for the Cabinet Office, made the comments as he was challenged over the differences in the current rules on declaring benefits received by ministers and MPs, along with Commons Leader Mark Spencer.

The pair agreed it was worth debating whether ministers should be required to record their financial interests on a more regular basis, but insisted the existing process was “transparent”.

Mr Ellis was met with exasperation from the Commons Committee on Standards when he sought to explain why some benefits would be registered in a ministerial capacity, and others not – arguing connections could be drawn between a James Bond film and “executive function”.

Asked why Ms Patel registered tickets to a Bond premiere in her capacity as a minister, rather than as an MP – the latter of which would require speedier disclosure to the public – Mr Spencer said: “I think it’s fairly obvious that she was invited then as the Home Secretary.”

Mr Ellis added: “The nature of the film one could argue is connected to executive function.”

As it stands, ministers do not need to register gifts received in their “capacity as a minister” in the House record, with departments instead expected to publish the details on a quarterly basis.

By contrast, any change to MPs’ interests must be registered within 28 days.

Mr Spencer said the “timeliness” of the reporting was “worthy of debate”, while Mr Ellis agreed it was “definitely something to look at”.

But Mr Ellis stressed that it was important to recognise the “separation of powers” where the registration of interests was concerned.

“Of course, we hold strongly to the view that ministers are of the executive branch and that is distinct and separate from the legislative branch, and therefore it is right that there are two separate processes – as there is of course for the third branch, which we tend not to talk about, but obviously exists: the judiciary,” he said.

He said ministers should declare any gift to their private office “as and when it’s given, or very soon thereafter”, but acknowledged publication of this information would come later.

Mr Spencer said it was “worthy of challenge” that reporting should be “on a more regular basis”.

“I think that is a worthy challenge and debate to have,” he said.

Mr Ellis added: “I agree with the Leader that it’s definitely something to look at, in terms of the timeliness of the publication.

“My starting point is, though, from my point of view … that the actual declaration takes place when it’s declared at the private office level, even if it’s not viewable by the public at that moment.”

Pressed on why there should not be a “really simple system” whereby ministers’ and MPs’ declarations were subject to the same 28-day timescale, Mr Spencer said both existing means were “transparent”.

“Whichever register I put them on, they’re both transparent,” he said.

“They’re both recorded. They’re both available to the public. Where we disagree, or where we’re debating, is the timeliness of that reporting – and I said to you right at the beginning of this debate, I’m up for that debate, and I’m up for that challenge of whether or not it should be more speedy.”

Mr Ellis said he did not think it made “an awful lot of difference” how often ministers’ interests were registered.

Asked how much it inspired public confidence that these details were published less frequently, and in a “chaotic manner”, compared to the Commons’ approach, he said: “If I may suggest, I don’t think it makes an awful lot of difference.

“Because we have an extremely robust system … if there was some impropriety when that information was released, then it wouldn’t matter whether it was last month, last week, or six months ago. That would be highlighted.”