"We are still open having a customs union with the UK. Such a customs union would eliminate an important part of custom checks," he said.
But in the meantime, under the EU vision of a Brexit deal, companies on the British mainland shipping goods to Northern Ireland will fill out "customs declarations online and in advance." "The only visible systematic checks between Northern Ireland and the rest of the UK would involve scanning the bar codes on lorries or containers, which could be done on ferries or in transit ports," he said.
Regulatory checks on industrial goods produced within Northern Ireland for export to the EU could be carried out by "market surveillance regulators" at the factory, rather than at the border.
Finally, existing health checks on animals arriving in Northern Irish port would remain in place, but would have to be stepped up to cover 100 percent of shipments rather than 10 percent now.
The British sh leader is under pressure to agree an exit deal before March 29 next year, but the Northern Irish party upon which she depends for her majority reportedly threatened Wednesday to vote down the national budget later this month if she gives away too much.
Sources in the Democratic Unionist Party (DUP), which has ten MPs, told the BBC and Sky News they were prepared to break their agreement to support the government in budget matters if May breaches their red lines in Brexit talks.
Getting a budget approved by the House of Commons is traditionally a test of confidence in a government, without which it could fall.
Shortly before the reports emerged, when asked if the government could rely on the DUP, a Downing Street spokesman said: "The confidence and supply agreement that we have with the DUP is a matter of record."
A DUP spokesman said: "The government is well aware of our position on this issue. Our position hasn't changed and we don't expect the government will change its position.