In his first overseas visit to a fellow leader, Mr Johnson is meeting Mrs Merkel after he told the European Union the backstop - which aims to prevent a hard Irish border after Brexit - must be ditched if a no-deal exit was to be avoided.
Merkel has promised to discuss "practical solutions" to the Irish border insurance policy or "backstop" that Johnson says is unacceptable - but she said the Withdrawal Agreement will not be reopened.
"Why not? Then we're a long way ahead", said Merkel, adding that border controls between Northern Ireland and Ireland would become superfluous and that the integrity of the single market could be safeguarded if Britain and the European Union re-define their future relations.
Speaking on RTE Radio One, Mr Coveney said the Irish would not be "steam-rolled at the end of this because a British prime minister has rolled out new red lines". Instead of honouring the promise made to the British people in parliament over 100 times by taking the country out of Europe on that day, Theresa May chose to delay Brexit instead. She also reiterated that there would be no change to the withdrawal agreement.
After meeting with Merkel, Johnson goes to Paris tomorrow for talks with French President Emmanuel Macron, then on to a three-day summit of G-7 leaders, including US President Donald Trump, which begins Saturday in Biarritz, France.
The incentive to improve ties with the United Kingdom ahead of developments in parliament do not make sense as there is the prospect of the Johnson regime being deposed in a no-confidence vote.
Earlier this month, senior Trump aide John Bolton visited London carrying a message from his boss that the United States would set aside foreign policy differences and focus on doing whatever it could to help Britain through the Brexit process.
A French presidential aide added that a no-deal Brexit was fast becoming the most likely scenario.
Johnson proposed that the backstop - part of the withdrawal agreement his predecessor, Theresa May, agreed a year ago - be replaced with a "commitment" to invent and implement an as-yet-unknown solution in an as-yet-undefined transition period as part of a post-Brexit relationship.
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He debunked Putin's claims and argued that unlike in Moscow, France allows members of the opposition to run for office. France is seeking to play the role of mediator in Russia's conflict with Ukraine.
Speaking to reporters on Tuesday (20 August), a European Commission spokesperson said that while the EU executive "welcomed the United Kingdom government's engagement and commitment to an orderly withdrawal", the letter contained no new proposals.
European Commissioner for Agriculture Phil Hogan has said the EU will "not buckle" in the face of a no -deal Brexit.
"We've made it clear 1,000 times we don't want to see any checks on the Northern Irish frontier at all", Johnson told ITV.
But in a tweet, Tusk dismissed his suggestion, saying: "Those against the backstop and not proposing realistic alternatives in fact support re-establishing a border".
Merkel said the backstop was intended only as a transitional rule for the not finally resolved Ireland issue.
He said the British government's only Churchillian legacy in the event of a no-deal Brexit will be "never have so few done so much damage to so many".
Given the shock and dismay Brexit has sparked in continental Europe, its vocal champion, the flamboyant former London mayor and ex-foreign minister Johnson, has also faced broad criticism in Europe.
The Communities Secretary told Today: "I think the European Union would be ill-advised to under-estimate our determination to do so or the degree of preparedness that we are undertaking at the moment".