EU warns trade sanctions are an option to make Boris Johnson stand by his Brexit deal

The president of the European Council has said the EU will use "all the tools we have" to defend its interests ahead of a meeting with Boris Johnson over implementing the Brexit deal.

Charles Michel told a press conference at the G7 in Cornwall that the UK would be violating "rule of law" if it did not stand by the agreement it signed on Northern Ireland.

The comments, a coded threat of trade sanctions included as a mechanism in the treaty, come as the UK drags its feet on implementing the controversial protocol – which was hailed by Boris Johnson as a triumph at the time it was signed.

The Brexit deals signed between the UK and EU contain specific provisions that allow negotiated trade rights to be suspended if one side or the other does not stand by its other commitments. The sanctions would have to be implemented through an agreed arbitration process also outlined in the treaty.

Britain wants to suspend or change certain provisions in the Northern Ireland protocol negotiated by the prime minister just a year ago because it says it is more damaging to the territory than had been expected.

But speaking alongside her colleague on Thursday morning European Commission president Ursula von der Leyen said the EU had "bent over backwards for years" to accommodate the UK.

She urged the UK to, as agreed, build the necessary infrastructure to carry out checks on trade, give the EU access to IT systems, and end "unilateral measures reapplying some aspects of the protocol".

She told reporters: "We agreed with the United Kingdom that the protocol was the only solution ensuring the absence of a hard border in Northern Ireland. We've been really debating that for years, and we've found the one and only solution. We have a treaty on that, the withdrawal agreement, it has been signed by both sides. Pacta sunt servanda. It is important that we now implement the protocol."

Mr Michel, who represents EU leaders collectively, told a press conference: "Member states in Europe are expressing more and more worries about the current situation. Because indeed, it is fundamental, it is paramount to implement what we have decided. This is a question of rule of law, which is an important value that we share in common.

"The Good Friday Agreement is of course a priority. We want to make sure that this ... will be fully implemented, and it's very important for the European Union to implement what we have decided, to be a loyal partner, but at the same time: we will use all the tools we have in order to make sure that we defend our interests, that we protect the integrity of the single market and that we guarantee the level playing field."

Boris Johnson's Brexit chief David Frost is planning to attend the G7 alongside the prime minister for the planned trilateral meeting with the EU and US – a sign that discussions will be in-depth.

US president Joe Biden, who has taken an interest in the Northern Ireland issue, is expected to tell Boris Johnson to stand by his commitments. It comes amid reports that senior US embassy diplomats in London have already told Lord Frost the UK may inflame tensions by refusing to implement the deal.