Through the project, he said donations had been taken in for refugees from Ukraine and they now had enough “to fill a small lorry with everything from nappies to sanitary products, warm clothes to first aid kits”.
Posting a photograph sitting behind the wheel of the lorry, Mr Cameron said: “I’m currently driving to Poland with two Chippy Larder colleagues to make our delivery to the Red Cross.
“It’s going to be a long drive, but I’ll keep you updated along the way.”
Earlier this week, Mr Cameron called for more humanitarian help to be given to Ukraine.
Speaking to Channel 4 News, he called on the Government to “get back” to dedicating 0.7% of gross national income (GNI) to overseas aid, after it was cut to 0.5% last year.
Mr Cameron said the Cabinet should have an aid minister, who would be “100% dedicated” to the role.
Chancellor Rishi Sunak has promised to return the UK’s aid contributions to 0.7% by the end of this Parliament.
But Mr Cameron said: “Let’s do more on humanitarian aid. We achieved 0.7% of GDP in our aid payments. I’m sad we’ve got away from that. I hope we can get back there.
“Let’s – with the EU – lead the donor conference, lead the aid effort.
“Let’s have a dedicated aid minister in the Cabinet doing development.
“The Foreign Office ministers do a great job but it’d be good to have someone who’s 100% dedicated to humanitarian aid and development.”
He also said permanent Nato bases should be created in Estonia, Latvia and Lithuania.