UK tested Channel ‘blockade’ to deter migrants, leak reveals

Trials have taken place to test a blockade in the Channel similar to Australia’s controversial “turn back the boats” tactic, according to official documents seen by the Guardian.

The documents, produced in mid-September and marked “official” and “sensitive”, summarise advice from officials who were asked by Downing Street to consider “possible options for negotiating an offshore asylum processing facility similar to the Australian model in Papua New Guinea and Nauru”.

In August it was reported that the home secretary, Priti Patel, was planning to approach French officials for cooperation in using Royal Navy and Border Force boats to block the path of refugees and migrants attempting to reach the UK in small boats.

The document reveals this approach has been trialled. It reads: “Trials are currently under way to test a ‘blockade’ tactic in the Channel on the median line between French and UK waters, akin to the Australian ‘turn back’ tactic, whereby migrant boats would be physically prevented (most likely by one or more UK RHIBs [rigid hull inflatable boats] from entering UK waters.”

The Australian policy was developed by the country’s former prime minister Tony Abbott, who was recently appointed as a UK government trade adviser. Operation Sovereign Borders involves turning back boats to the country of embarkation before they reach Australian waters.

Related: UK offshore detention proposal could create 'human rights disaster', Australian experts warn

The Australian government considers the policy to be successful but it has been met with severe criticism from human rights groups. The Home Office has been approached for comment.

The documents have been revealed by the Guardian at a time of increased tension over the UK’s asylum policy. Seven thousand migrants have arrived in the UK in small boats across the Channel so far this year, according to PA Media analysis – more than three times the number of arrivals by this route in the whole of 2019.

The UK government has also launched a consultation with the maritime industry to explore constructing floating walls in the Channel to block asylum seekers from crossing the narrow strait from France, the Financial Times reported.

An email from the trade body Maritime UK, obtained by the newspaper, reveals that the idea of floating barriers is being seriously pursued by Home Office officials. Maritime UK told the Guardian it had informed the Home Office that it did not think the proposal was “legally possible”.

A Maritime UK spokesperson said: “As the umbrella organisation for UK maritime, we are a conduit between industry and government and are often asked by government for advice or input on policy matters. The Home Office engaged us to pass on a question around options to inhibit passage to UK territorial waters, which we gave to our members. The clear view, which we shared with the Home Office, was that as a matter of international convention, that this is not legally possible.”

Downing Street said it would not comment on each of the leaked measures but said the government would soon bring forward “a package of measures” to address illegal migration once the UK has left the EU.

The prime minister’s spokesman said: “We are developing plans around illegal migration and asylum to ensure that we’re able to provide protection to those who need it, while preventing abuse of the system and the criminality associated with it.

“That includes looking at what a whole host of other countries do. But the work is ongoing. There’s an awful lot of speculation around today and I don’t plan on adding anything beyond that.”

Downing Street said it did not recognise some of the more outlandish reporting – including the possibility of a wave machine in the Channel to push back migrants in small boats. “These things won’t be happening,” the spokesman said.