Macron was hosted by British Prime Minister Theresa May at the meeting which focused on migration, terrorism, defence and climate change.
Nothing groundbreaking was expected of the meeting - it was really about showing that bilateral relations were still alive and kicking.
"Some of the discussion around more cooperation in terms of migration and managing the Calais border, these are discussions that have taken place in the past, particularly in recent years, with the increased pressure on the Calais border following the EU migration crisis, this is a topic that has come to the fore," Aarti Shankar, a policy analyst at the Open Europe thinktank, told RFI.
Shankar said that once the UK leaves the EU, more meetings like this one are likely.
"More rounds of discussion on the management of this border will take place and perhaps not just in terms of migration, if the UK follows through on its intention to leave the EU customs [union] as well we might find that more bilateral cooperation occurs in terms of customs cooperation as well."
Money for security
The 50 million euros in British funding will go towards fencing, CCTV and detection technology in the northern French port city as well as at other spots along the Channel.
The UK has also said it would give France money to help in the Sahel region. There are several reasons behind the move.
France has invested heavily in the region, with its Operation Barkhane, and several European countries have contributed troops too.
Now the UK is willing to give some money and helicopters to help out as well.
"This is a great contribution - and an important gesture," said Paul Melly, a West Africa analyst at the Royal Institute of International Affairs in London.
Melly said it was also part of the broader picture.
"There's the question of terrorism risk to Europe and also to West Africa itself because after all, Africa is Europe's neighbour continent so long term security problems in Africa will always have a security implication for Europe."
He said that the question that is going to be very difficult to tackle is about migration and making progress with development in the poor regions in the Sahel.
"So that people don't feel the need to migrate unless there is security. And although Britain takes a very tough line on migration, has not accepted migrants who have for example moved across the Mediterranean into southern Europe, overall, in terms of reducing migration pressure on Europe, better security in the Sahel is a key component."
Melly says it comes at a crucial time - the G5 Sahel members (Mali, Niger, Burkina Faso, Chad, Mauritania) are stepping up their own forces, so additional help is more than welcome.
It also aims to consolidate bilateral relations with France, a much needed ally for the UK post Brexit, according to counter-terrorism expert Yan St Pierre.
"It has less to do with the agenda in the region itself than with trying to re-establish very good bilateral relations with France. The G5 project for France is extremely important and I think that for the UK to invest in France's project, for lack of a better expression, is a show of good faith."
St Pierre added that this was something France needs, and Macron has been pushing for a European army.
"It's a way for him to say, 'Invest in our projects, we'll show you that we can do things well, establish something good going forward and for the UK, investing in France's project in the Sahel is a step in that direction."
St Pierre also says that it is in Britain's interest to maintain good relations with EU countries, starting with France, especially because of the lack of clear foreign policy from the US.