Prime Minister Boris Johnson reached out to French President Emmanuel Macron for a telephone call, after Paris accused its UK, US and Australian allies of a "stab in the back" and dismissed London as a "junior partner" to Washington.

Johnson and Macron "reaffirmed the importance of the UK-France relationship and agreed to continue working closely together around the world on our shared agenda, through NATO and bilaterally," Downing Street said in a statement.

They also noted the "strategic significance" of UK-French cooperation in the Indo-Pacific and in Africa, it said.

They agreed also to "intensify cooperation" against cross-Channel people-smugglers, and to stay in contact over post-Brexit fisheries licences and trading arrangements for Northern Ireland.

Macron was left furious last week after Australia ditched a mega-deal to buy diesel submarines from France in favour of American nuclear-powered ones, under an agreement secured during secret negotiations facilitated by Britain.

The contract forms the centrepiece of a new strategic alliance involving Australia, Britain and the United States known as AUKUS, which is widely seen as an attempt to counter China in the Indo-Pacific.

France and other NATO allies are not in the mix, although the AUKUS trio have stressed it is not meant to be exclusionary.

In a terse account of the Johnson call, Macron's office said the prime minister offered to "re-establish cooperation" and that the French president was "awaiting his proposals".

- 'Prenez un grip' -

French anger over the submarine contract saw Macron recall the French ambassadors to Washington and Canberra in an unprecedented diplomatic protest.

But the French envoy in London remained at her post, with France's Europe Minister Clement Beaune dismissing London as a mere "third wheel" in the deal.

Using franglais, Johnson this week appealed to France to "Donnez-moi un break", calling for calm after tempers flared in France, while also telling Paris to "prenez un grip" ("get a grip").

The submarine spat brought relations between Paris and London to their worst since Britain's 2016 vote to leave the European Union.

Brexit has led to several disagreements between both nations, notably over fishing rights but also the issue of trade between mainland Britain and Northern Ireland, which came to a head during the G7 leaders' meeting in June.

Migrant flows have also been a major irritant between Paris and London.

There remains, however, a willingness on both sides to continue close cooperation in defence matters, experts say.

The submarine deal "created a legitimate anger in France and clearly dealt a serious blow to trust and cooperation between France and the UK in a relationship already strained by years of post-Brexit disputes", said Hans Kundnani and Alice Billon-Galland, analysts at the Chatham House policy institute.

But they said "the reality is the two countries share a similar set of interests and partners in the Indo-Pacific and beyond, and will need to find ways to navigate current tensions".

If they succeed that could open the way for other Europeans to also contribute to security in Asia, they said.

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