First Minister Alex Salmond is to be called before a Scottish Parliament committee over Donald Trump's £1bn Aberdeenshire golf resort plan.
Mr Salmond met team Trump as the local MSP
Holyrood's local government committee decided to investigate the Scottish Government's intervention over Mr Trump's development on Menie estate.
SNP ministers decided to have the final say over the plans, after they were rejected by the local council.
Several other senior government figures will also appear before the committee.
Opposition parties said the issue of whether there had been improper behaviour had to be looked into, following a series of events surrounding the application.
A spokeswoman for Mr Salmond said: "The first minister has previously said that he is very open and available to parliamentary committees, as are all ministers, and is perfectly relaxed with this because ministers and civil servants have conducted themselves totally correctly throughout.
"There is no difficulty with this, subject to nothing being done to prejudice a live application currently before government, and of course Mr Salmond has no role in the planning decisions of this proposed development."
MSPs will call Scotland's chief planner Jim McKinnon and Aberdeenshire Council chief executive Alan Campbell, to give evidence.
Finance Secretary John Swinney, who will make the final decision on whether the Trump application gets the go-ahead, will also appear before the committee.
Nationalist MSP Kenny Gibson endorsed the committee's proposals, put forward by Tory parliamentary business manager David McLetchie, saying the controversy had been "rumbling on long enough".
Mr Salmond met Mr Trump's representatives the day before ministers decided to "call in" the golf resort plans, following its rejection, on a casting vote, by Aberdeenshire Council's infrastructure committee.
The first minister is forbidden from taking part in the planning process but insisted that, because the plans for two championship golf courses, 950 holiday homes and 36 golf villas fell into his Gordon constituency, he was duty bound to meet people on all sides.
It also emerged that, on the day ministers called in the Trump application, Aberdeenshire Council confirmed that, at the start of a phone call with Mr McKinnon, it emerged Mr Trump's team was also present.
Mr Trump's plans were called in by ministers
The government later said members of the Trump organisation were in the room with Mr McKinnon at the start of the first of two phone conversations, but not when the discussion took place.
Mr McLetchie said: "It's important to stress it would certainly not be our role to consider the merits or de-merits of this particular application but to look solely at the process by which it has been handled, about which I think there are genuine public concerns, not just in relation to people in the north east of Scotland but, indeed, across Scotland."
Liberal Democrat MSP Robert Brown said the inquiry should focus solely on the handling of the application.
Labour's Johann Lamont added: "One of the things that strikes me is the degree of abuse in some cases against the councillors who have taken this decision at a local level has been quite significant.
Mr Gibson said the process should be carried out as soon as possible.
"I think it is important that we put as much information as we can into the public domain and I think there is no better way to do it than actually have the first minister and the cabinet secretary at committee," he said.
The committee is to take legal advice and wait for the answers to a series of parliamentary questions before calling the witnesses at its meeting on 16 January.