Huddlestone, who has been capped four times for England, is in Hull discussing terms with Tigers representatives.
The club are unwilling to disclose the fee agreed for the 26-year-old, but Press Association Sport understands it at least matches their £5million record signing of Jimmy Bullard.
Hull boss Steve Bruce has been busy in the transfer market since winning promotion to the Barclays Premier League, but has so far shopped prudently.
Former Birmingham centre-half Curtis Davies, who came in for £2.25million, has been his most expensive addition to date with a combination of free transfers, loan deals and cheaper arrivals such as Yannick Sagbo and Allan McGregor ensuring Bruce has operated well within budget.
But he has made it clear that midfield is an area which needs significant bolstering, especially since the departures of Corry Evans and Tom Cairney to Blackburn and a pre-season injury to Stephen Quinn.
'You're always looking, that's the manager's job...always wanting one more,'' Bruce told Sky Sports News on Tuesday.
''We're a little thin on the ground in midfield areas. We've let a couple out and it's one area we are looking to strengthen. Hopefully by the time the window shuts we'll get two or three bodies in that department to help us.''
Huddlestone fits the bill as a player who can play as a midfield anchor who is also comfortable on the ball and Bruce would consider it money well spent if he can come to an agreement with the former Leeds man.
Sunderland were also on the lookout for such a player and Black Cats boss Paolo Di Canio had upped his interest in Huddlestone only to see Hull make a more decisive move this week.
Source: PA
Source: PA