A contract will be signed today to allow the phased release of £315million from the Inverness City Region Deal.
UK and Scottish government ministers will travel to Invergordon for the signing ceremony.
The head of terms agreement for the cash injection was struck in March last year, but a second, more detailed document has been produced to “underpin” and unlock the investment.
New information about the first projects to benefit from the investment will be announced to coincide with today’s event.
Scottish Economy Secretary Keith Brown, Scotland Office Minister Andrew Dunlop and Highland Council leader Margaret Davidson will sign the deal at the premises of Carbon Dynamic in Invergordon.
Last October, Highland Council revealed it had lodged five business cases, worth a total of about £48million from the City Region Deal, with the two governments in London and Edinburgh.
They included a request for an initial £10million for remedial work at the former Longman landfill site to pave the way for a new industrial estate and more than 2,000 jobs.
There was also an application for £15million to turn Inverness Castle into a tourist attraction, a pitch for £11million to create a “Northern Innovation Hub”, as well as a request for £3million to help create a new Science Skills Academy, and another to deliver a new School of Health, Social Care and Life Sciences.
City Deals aim to give new powers and freedoms to the UK’s cities, and were first launched by then-deputy prime minister Nick Clegg in December 2011.
Glasgow became the first Scottish city to benefit from the lucrative package in 2014, and was followed by Aberdeen and then Inverness.
Other commitments in the Highland agreement include the delivery of the new A9/A96 link road between Inshes and Smithton, a flyover at the Kessock Bridge roundabout, and West Link road improvements.
The local authority received an advance of £3million in 2015-16, and £666,000 of it was spent on developing various projects, including the Inverness Castle revamp and wifi for Inverness city centre.
Some councillors have previously questioned the level of transparency over the funding, and whether communities outside the Highland capital will benefit.
