[1] By the start of the year the majority of the invasion forces brought together for this had been diverted to join the French campaign in Egypt and Syria, but enough remained to cause worry.

[2] Prime Minister William Pitt the Younger and his government, aware of the invasion flotilla that had been built up in France and the Batavian Republic, put out requests for solutions to halt or defend against Napoleon's plans.

[1] In April a proposal was put forward by General Sir Charles Grey, the commander of the British Army's Southern District, for offensive anti-invasion operations.

[1][3] In order to avoid attacks by Royal Navy warships in the English Channel, the French were moving their invasion craft from Flushing to Ostend and Dunkirk using the newly expanded Bruges–Ostend Canal.

[2] Grey put forward the plan on the recommendation of Captain Home Riggs Popham of the Royal Navy, who suggested that an amphibious landing be made at Ostend where they could then destroy the canal's basin gates and the new sluices.

This would hamper the operational capability of the canal and interrupt French maritime movement between Holland, Flanders, and France, stopping the Dutch part of the invasion flotilla from assembling.

The Admiralty had initially promised that this force would be prepared and brought together for Popham before the end of April, within ten days of the plan being finalised, but this was not actually completed until four weeks later on 13 May.

[6] A separate group of warships was initially planned to go to Dunkirk to ensure that no enemy ships could escape there to defend Ostend once the attack was underway, but this was later abandoned.

Intending to make a quick crossing of the English Channel, the ships were initially halted in this action by a violent gale off the coast of Kent, and only reached their destination on 16 May.

The rest of the ships and Coote's soldiers would then be left to the main attack, for which Popham attached a naval brigade formed with seamen from his largest vessels to bolster it.

The expedition stayed at sea for another two days before on 18 May a captured ship revealed to Popham and Coote that the invasion craft at Flushing were making haste down the canal for Ostend and Dunkirk.

[10] Hearing the news, Coote begged Popham for the landings to go ahead, expecting that by the time their mission had been completed the weather would have quietened enough that the troops could reembark safely.

Major-General Harry Burrard then succeeded with some of the Guards light infantry, 23rd and 49th grenadiers, and two field guns in securing the approaches to the harbour, despite attacks from a multitude of sharpshooters.

Seeing that further attempts to get to sea were hopeless and expecting that the weather would moderate on the following day, Coote formed a position on the sandbanks, facing inland.

Despite the failure to rescue Coote's force, naval historian Sir Julian Corbett argues that as the destruction of the canal gates had the impact they had intended, the expedition was "a thoroughly well-designed, and brilliantly-executed enterprise".