He said some had claimed bad weather was the biggest factor in a reduction of crossings this year.
“But what that demonstrates is absolutely that the French are being effective in preventing a number of these small boats.”
“Clearly, every single day that one slips through the net and crosses, it’s one too many, and that’s why it’s absolutely critical to us to not take our foot off the gas and to keep working hard with our French partners and stop this from happening.”
In the last week, 425 migrants made it across the Channel on five boats during three days of good weather.
Stopping the trade in equipment for Channel crossings is the first layer of tactics being used by the UK and other countries.
Dinghies, outboard engines, and life preservers have been seized by police in Germany.
Nearer the coast, boats have been discovered buried on beaches and in cars heading for the coast.
With less equipment available, people smugglers have resorted to using bigger boats.
Earlier this month a “mega-dinghy”, with 230 people on board, was intercepted in the Channel.
The second layer is to stop migrants launching from beaches.
In July last year a BBC team witnessed the police slashing an inflatable boat with a knife to prevent it being used. This technique is now being used more often.
Interception at sea is the most difficult challenge. The UK government knows if it can prevent migrant boats getting into British waters, where the Border Force is legally obliged to pick them up, the incentive to try to cross will be reduced.
The concern is that smuggling gangs will continue to adapt but Eastaugh told the BBC that changes to their methods demonstrated how hard they are finding it to operate.
“That’s why the numbers we’re seeing are so successful, and we’re absolutely not complacent, and we must keep working this way to keep the numbers down,” he said.
Shadow home secretary Chris Philp said: “The only way we can stop the crossings is by having a proper deterrent. If people know they can stay in the UK, get put up in a hotel and claim benefits then they will keep risking these dangerous journeys.”
Earlier this month Reform UK said if it was in power it would intercept boats crossing the English Channel and return migrants to French ports, even if France disagreed.
The French interior ministry responded by saying it would “constitute a violation of French sovereignty”.
