The River Termon, which forms the border between Northern Ireland and the Irish Republic and divides the village of Pettigoe in two | Paul Faith/AFP via Getty Images UK to unilaterally waive all checks at Irish border in no-deal Brexit Temporary regime would permit unmonitored flow of goods and exploitation of the new system by smugglers, officials acknowledge.

LONDON — The U.K. would unilaterally waive checks on all goods crossing the Northern Ireland border in the event of a no-deal Brexit, as part of a temporary regime in the days immediately after the U.K.’s exit, ministers said Wednesday.

In such a scenario, the U.K. would seek to immediately enter talks with the EU and the Irish government to find a long-term solution, according to a government briefing.

The temporary regime would permit the unmonitored flow of goods and exploitation of the new system by smugglers, officials acknowledged.

Tariffs which would apply to 13 percent of imports in the event of no deal would not be levied on goods crossing the Northern Ireland border. The existing VAT regime for traders would remain in place, and small traders not currently registered would be allowed to report online only periodically.

However, animal and animal products from outside the EU would need to enter Northern Ireland through a designated port. There would be new import requirements on a small number of goods, such as endangered species and hazardous chemicals, but these would not involve infrastructure or checks at the border, the government said.

After Theresa May’s Brexit deal was rejected by the House of Commons for a second time Tuesday, MPs will vote later Wednesday on whether to leave the EU with no deal on the legal date of March 29.

Northern Ireland Secretary Karen Bradley said the measures “can only be temporary and short-term.”

She added: “We will do all we can to support people and businesses across Northern Ireland in the event that we leave without a deal."

CORRECTION: This article was updated to correct the percentage of imports that would attract tariffs, which is 13 percent.