The event is scheduled for 12 and 13 September with several UK ministers expected to take part.
However, without a functioning executive at Stormont there will be no Northern Ireland ministers in post.
Ulster Unionist Party leader Doug Beattie had asked the government to delay the summit.
This would allow more time for Stormont to be restored, he said.
But some businesses have said they do not want the event to be postponed while political negotiations continue without an end in sight.
Northern Ireland has been without devolved government since February 2022, when the Democratic Unionist Party walked out in protest at the Northern Ireland Protocol.
The protocol was a 2019 agreement which kept Northern Ireland inside the European Unionʼs single market for goods but created a trade border in the Irish Sea.
Earlier this year the UK and EU signed up to a renegotiated deal, the Windsor Framework.
Some of the frameworkʼs major operational aspects are due to be implemented from October.
They include the expansion of a trusted trader scheme and a system of green lanes and red lanes for managing the flow of goods at Northern Ireland ports.
The government has said the summit will build on the Windsor Framework, with investors from the US, Middle East, Europe and Asia all due to attend.
The event will hear from Northern Ireland Secretary Chris Heaton-Harris, Housing and Levelling Up Secretary Michael Gove and the US Economic Envoy to Northern Ireland, Joe Kennedy.
Business Secretary Kemi Badenoch is also expected to appear.
It is not clear whether the prime minister will take part, but earlier this year Rishi Sunak sold the Windsor Framework as a "decisive breakthrough" that would provide new opportunities for businesses.
Investment Minister Lord Johnson said the event would "provide rocket fuel for Northern Ireland businesses to launch into new frontiers" across technology and finance sectors.