Michel Barnier has expressed his frustration with Dominic Raab, the Brexit secretary, for allegedly withholding information from the EU, as the question of the Irish border erupted again in the Brexit negotiations.

The EU negotiator was said to be “disappointed and irritated” by Raab’s alleged failure this week to live up to a promise to provide data on the trade flows between Northern Ireland and the rest of the UK, which had been requested as part of an attempt to take the drama out of the Irish border issue.

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The backstop solution for avoiding a border between Northern Ireland and the Republic would result in the former effectively staying in the customs union and single market for goods as the rest of the UK withdraws. The British government has dismissed the backstop as it would “dislocate” the UK by creating a border in the Irish Sea.

Barnier requested the trade data as he believes it will show that very few goods going between Britain and Northern Ireland go directly to Belfast. The European commission’s officials want to show that the number of checks needed in the Irish Sea would therefore be small and that talk of a border in the Irish Sea is overblown.

Raab had agreed to provide the information last week, but arrived empty handed to talks on Thursday. An EU official said Barnier had been disappointed, later telling the member states that the UK was not “helping itself” over the issue.

On Friday evening a spokesperson from the Department for Exiting the European Union said: “We will share this information with the commission shortly.”

A transcript of evidence given to the Brexit select committee by Barnier on Monday revealed that he wanted to “look at the individual controls that are necessary” and to see “how and when and where these controls would take place”.

Barnier told the committee: “They could be dispersed. They could take place in different places, on board vessels, in ports outside Ireland, they could be done using technological means, they could be dispersed, as I said, or simplified in technological terms.”

David Phinnemore, the professor of European politics at Queen’s University in Belfast, said Barnier was trying to de-dramatise the border issue. “We have here an attempt by Barnier publicly to encourage the UK to think how controls could be implemented/managed and draw it out of the rhetoric of ‘no hard border in the Irish Sea’ and the backstop undermining the constitutional integrity of the UK,” he said.

Barnier’s deputy negotiator, Sabine Weyand, gave examples such as fish and bicycle imports to illustrate why checks would be necessary if the border with the Republic stayed open.

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The EU would need to stop goods exiting Britain and entering Ireland and possible onwards on smuggling routes to the continent. This was for standards and public health reasons, she said.

“Here we are talking very practically about – imagine – an import of shrimps from an Asian country where they treat shrimps with antibiotics, which are prohibited in the EU because they can lead to blindness.

“Now this shipment arrives in Liverpool and is destined for the market in Northern Ireland and also the EU27. At what moment, and how, do we check that there are no residues of prohibited antibiotics?” she said.

Relations between Barnier and Raab were already strained over the Irish border, with the two men engaging in a heated debate two weeks ago which sources suggested had marked a low point in the discussions.

The latest row suggests that the two sides are no closer to resolving the issue. Barnier has warned that a failure by the UK to sign up to a workable backstop will mean a no-deal scenario.

Rather than working on the Irish, the UK negotiating team instead focused this week on trying to convince Barnier of the merits of the central planks of the Chequers plan under which there would be frictionless trade in goods. There would also be a customs arrangement that would prevent checks on imports and exports and allow the British government to pursue an independent trade policy.

Barnier has said that these proposals present a threat to the European project and has expressed his strong opposition. He told the cross-party committee of MPs: “Your proposal does not seem workable to us, basically.”

• This article was amended on 10 September 2018. An earlier version stated that the government had promised to provide data on the trade flows between the UK and Northern Ireland. As Northern Ireland is part of the UK, it should have said “the rest of the UK”. It also referred to Britain as the mainland, contrary to Guardian style. These errors have been corrected.