Relations have never been as bad between Ireland and UK government ministers, according to Tánaiste Leo Varadkar.
He told BBC Northern Ireland's The View programme he believes the UK is "not being even handed" when it comes to the Northern Ireland Protocol.
MPs voted earlier this week to give the Northern Ireland Protocol Bill a second reading. The legislation is designed to override parts of the post-Brexit deal to allay concerns over its impact on the UK.
It comes after the DUP said it will not nominate ministers to allow a new Stormont Executive until the UK takes actions on its concerns around the protocol.
However the move by Britain has been branded as illegal and a clear breach of international law.
Mr Varadkar said the UK's bid to unilaterally change the protocol was a "strategic mistake" and that the EU would "not be threatened" by the UK's approach to the ongoing stand-off.
"The British government had given commitments in the past that it would be even handed in its approach to Northern Ireland," he said.
"I don't think that's the case when it comes to this government, they're siding with one of the three blocs of opinion that now exist in Northern Ireland.
"And I think that's a strategic mistake for people who want to preserve the union - to continue to impose things that a clear majority of people don't want means more people will turn away from the union.
"It's a peculiar policy coming from a government that purports to want to defend the union."
The UK government has not been "even handed" when it comes to resolving the row over the #NorthernIrelandProtocol, @LeoVaradkar has saidhttps://t.co/ZxyInC7CGN pic.twitter.com/3meeq2Owpw
— BBC News NI (@BBCNewsNI) June 30, 2022
Mr Varadkar also said that in his political lifetime, he had "never seen relations as bad" with UK ministers.
"I think trust needs to be restored, the best way they can do that is by de-escalating this.
"Even if you have difficulties trusting someone, you still have to try to come to an agreement. If we can't with this government, then a future government."
Earlier today, a former Downing Street chief of staff and architect of the Good Friday Agreement accused the British government of destroying its trust with the Irish government over the Northern Ireland Protocol.
Jonathan Powell, who worked for Tony Blair and was involved in negotiations that forged the peace deal, said the relationship between both governments was "terrible".
Mr Powell told the Oireachtas Good Friday Agreement committee that the compromises made in the 1998 accord had been "upended" by the impact of Brexit.
He said trust was vital to negotiations and had been crucial in the years leading up to the signing of the Good Friday Agreement.
He accused British Prime Minister Boris Johnson and his government of "casually destroying something through vandalism", and trashing the UK's reputation.
"We spent a decade building trust, but the current (British) government is spending its time destroying trust. It is catastrophic. The relationship is terrible but it can be restored quickly," Mr Powell said.
"Any new British government would do its best to rebuild relationships as it is so important."
He said the main casualty of the fall-out over the Northern Ireland Protocol would be the region's peace process.
The former British diplomat also said he was concerned it would induce a permanent political crisis that could prevent the re-establishment of the powersharing institutions in Northern Ireland.
Mr Powell said he "fears" it will take the departure of Mr Johnson before "serious negotiations" take place between the UK and the EU.
"Boris Johnson decided to opt for a border in the Irish Sea - something Theresa May had said no British Prime Minister could live with - in order to get a (Brexit) deal," Mr Powell told the committee.
"This option is certainly massively better than a border on the island of Ireland, which would be disastrous for the GFA (Good Friday Agreement), but it cannot be denied that it undermines the unionist sense of identity to have a border between Northern Ireland and the rest of the UK.
"Unfortunately for the unionists, no-one in six years of trying has been able to suggest an alternative.
"The current British government has embarked on a policy of escalation by threatening to unilaterally abrogate the NI Protocol which they themselves negotiated and signed.
"As a result, they have broken international law and undermined the UK's international reputation, alienated our allies in North America and Europe at a moment when we need them more than ever and potentially triggered a trade war when the world economy is struggling.
"The main casualty will be the NI peace process itself. That does not mean we are inevitably destined to return to the Troubles, but rather that it is likely to result in the institutions remaining broken for the foreseeable future, leaving NI without a viable government."
Fianna Fáil TD Brendan Smith described Mr Powell's comments as "stark". "It is a stark message from a former senior British diplomat," Mr Smith added.
"It's worrying for us because ... relationships between Ireland and Britain are at a low level."
Mr Powell also accused the British government of attempting to redefine consent and the cross-community consensus and agreement as contained in the peace accord.
He warned that changing the terms of the Good Friday Agreement would undermine its whole basis.
"It is dangerous to start changing powersharing at this stage given how sensitive it is. It is not wise to undermine consent and cross-community consent," he added.
