The government remains committed to putting its target of spending 0.7% of national income on overseas aid into law, Andrew Mitchell has told the BBC.
It was not in the Queen's Speech, but the international development secretary said the PM agreed "the law will come".
However, he said that this sort of "declaratory" bill should not take precedence over measures which were important for the UK's economic future.
He also unveiled a new UK aid logo featuring a union jack.
Mr Mitchell said the bill to put into law the UK's commitment to spend 0.7% of GDP on international aid was ready, and was awaiting parliamentary time.
"The key thing is we are standing by our commitments and from 2013 we will reach 0.7% - that's the absolute commitment," he told the BBC's Andrew Marr show.
"It will be put into law. The prime minister and I have made it clear the bill is ready to proceed and it will proceed when the business managers say."
When pressed on why it was omitted from the Queen's Speech, he told Marr: "In the end declaratory legislation should take secondary preference to the legislation which is being passed which is vital for our future economic prosperity."
'Investment in prosperity'
Mr Mitchell, who denied that the failure of the bill to appear was because of Conservative MPs opposing the idea, told the programme that foreign aid was an investment in the UK's future.
And he said there were plans to stamp British aid in future to show where it is from. It will feature a union jack and the words "UK aid, from the British people".
"It is important that all around the world, where British aid is saving and transforming lives, that the British public, the British taxpayer, gets the credit for this," he said.
He went on: "For under 1% of gross national income this is a tremendous investment, not only in the future stability and prosperity of some of the poorest and most dysfunctional parts of the world, it's an investment for Britain in Britain's future prosperity and stability and security."
Mr Mitchell defended the government's Big Society during the interview after the Archbishop of Canterbury, Dr Rowan Williams, denounced it as "aspirational waffle".
Asked if he thought the concept was a "cover for the withdrawal of the state under a Conservative-led government", he responded: "It is absolutely not that, it is the reverse of that and we don't always explain it perhaps as well as we should."
He added: "The archbishop and I will be announcing this week a joint effort between the government and all faiths on tackling poverty in the poorest parts of the world, we've been working on this for the last year.
"I think the headline belies the extraordinary amount of agreement on tackling poverty here and abroad which exists between this coalition government and the Church of England."
He also revealed plans for a family planning summit in London, which the government will co-host with the Bill and Melinda Gates Foundation, an organisation that funds health, development and education projects.
The aim is to halve the number of women in the poorest parts of the world who want access to contraception but do not currently have it, he said.
He said this would help 100 million women in these areas "make the decision for themselves".