The move is being spearheaded by Michael Moore, a Liberal Democrat MP and the former Scottish secretary, who is sponsoring a Private Member’s Bill that would place this duty on the state.

Speaking at the Institute for Public Policy Research in London last night, Moore called for cross-party consensus for his Bill.

Moore said it was ‘remarkable’ that the UK hit the target, adding that no other G7 country has hit 0.7%.

He noted that, in 2010, the UK spent £8.4bn on international development, equivalent to 0.57% of gross national product. This year, the projection is that the UK will spend £11.6bn meeting the 0.7% target for the second year running.

‘In a relatively short period of time we’ve seen a huge increase in the scale of the official development assistance that we grant to other countries,’ Moore said.

‘But significant challenges remain to the countries that we provide development assistance to and for the people who live in there.

‘So, I believe that this still makes the target relevant and why parties from Left and the Right and the centre from different perspective all support it till this day.

‘We’ve achieved the benchmark, [and] I strongly believe that we’ve got to make sure that we don’t slip back from that benchmark, hence the Bill.’

The purpose of legislating to protect the target is to allow government to shift the debate on to the quality of how aid is spent rather than how much is spent, Moore said.

However, he acknowledged that some critics maintain that public money should not be spent on international aid at all ‘when there are people facing difficulty at home’.

Moore will introduce the International Development (Official Development Assistance Target) Bill into the House of Commons on September 12. Attempts to pass the aid spending target into UK law have been made in recent years but were defeated.