The sacrifice of British troops in Afghanistan is not in vain as stability in the country is vital to the world, Helmand province's governor has said.
Speaking during a five-day visit to the UK, Gulabuddin Mangal said security in Afghanistan meant security in the UK.
He said he shared the pain of families of fallen British troops.
Sapper William Blanchard, of Gosport, Hants, was shot dead in the province on Saturday - bringing the total number of UK personnel killed since 2001 to 342.
The 39-year-old, of 101 (City of London) Engineer Regiment, was killed in the Nahr-e Saraj North area in the south of the country.
Speaking at the Foreign Office in London, Mr Mangal said: "The sacrifices of the international community are not for nothing.
"We have achieved a lot and I share the pain of families who have heard that their loved ones have been killed in Afghanistan.
"As a father I can feel how difficult it must be for a family to hear that their son or daughter has been killed."
He added: "Security in Afghanistan means security in the West and in the UK; we have got a shared common enemy."
Mr Mangal took control of Helmand two-and-a-half years ago and said security, education and agriculture had all improved since then.
During his visit, he is due to meet International Development Secretary Andrew Mitchell and Defence Secretary Liam Fox.
He will also lay a wreath at the National Memorial Arboretum on behalf of the people of Afghanistan to honour the commitment from British troops.