Emmanuel Macron has reacted angrily to Boris Johnson's public call for France to take back migrants who reach the UK.
The French President accused the UK prime minister of not being "serious" by making the call on Twitter, after the deaths of 27 people on Wednesday.
And his spokesman accused Mr Johnson of "double talk" for saying something different to Mr Macron privately.
The diplomatic row erupted after France withdrew a summit invitation to Home Secretary Priti Patel.
Belgium, France, the Netherlands, Germany and the European Commission are due to attend Sunday's talks in Calais, which Mr Macron set up to try to deal with the recent surge in migrant crossings of the Channel.
UK Transport Secretary Grant Shapps said France should re-invite Ms Patel, telling BBC Breakfast: "No nation can tackle this alone. I hope the French will reconsider [uninviting Ms Patel].
"It's in our interests. It's in their interests. It's certainly in the interests of people who are being people trafficked to the UK, with these tragic scenes we're seeing - people losing their lives."
The sinking of an inflatable boat on Wednesday marked the biggest loss of life by drowning in the English Channel in many years, with 17 men, seven women - one of whom was pregnant - and three children dying.
Ahead of Sunday's meeting, in a letter to Mr Macron on Thursday which was shared on Twitter, Mr Johnson set out five steps which he said could help avoid a repeat of the tragedy:
- Joint patrols to prevent more boats from leaving French beaches
- Deploying more advanced technology, like sensors and radar
- Maritime patrols in each other's territorial waters and airborne surveillance
- Deepening the work of the countries' joint intelligence cell
- Immediate work on a bilateral returns agreement with France, alongside talks to establish a UK-EU returns agreement
"An agreement with France to take back migrants who cross the Channel through this dangerous route would have an immediate and significant impact," Mr Johnson said.
But French Interior Minister Gérald Darmanin reacted angrily, saying: "We consider the British prime minister's public letter unacceptable and counter to our discussions between partners... As a result Priti Patel is no longer invited."
And a French government spokesman said the letter did not "correspond at all" with discussions Mr Johnson and Mr Macron had had on Wednesday, adding: "We are sick of double-speak."
On Friday morning, Mr Macron used a press conference to criticise the UK's handling of the crisis, saying: "The right response is to have a serious co-operation, to stop these movements, to dismantle the trafficking networks, and prevent these men and women arriving on our soil, because by then it's already too late."
He also attacked Mr Johnson over the posting of the prime minister's letter to the French government on Twitter, saying: "I spoke two days ago with Prime Minster Johnson in a serious way.
"For my part I continue to do that, as I do with all countries and all leaders. I am surprised by methods when they are not serious.
"We do not communicate from one leader to another on these issues by tweets and letters that we make public. We are not whistleblowers."
https://www.bbc.com/news/world-europe-59428311
