Celtic signed Eboue Kouassi for £2.8m

At midnight on Tuesday 31 January, this month's transfer window will close - or 'slam shut' for those of you of a more dramatic disposition!

There has been a fairly steady buzz of activity at most of Scotland's Premiership clubs throughout the last few weeks.

Many will be eager to push through another deal or two before the deadline, but if they fail to manage that, there is still a way to get new players on board outside of the transfer window.

Clubs are allowed to sign players who were already free agents (out of contract) before the transfer window closed, although a player cannot feature in official matches for a third club in the same season if he has already played for two others during this campaign.

Premiership clubs must complete any loan signings by the end of the January transfer window, but Championship, League One and League Two clubs are permitted to sign emergency loans (from within Scotland) after the deadline.

Here's a round-up of the top-flight transfer activity so far:

Aberdeen

In: The only arrival at Pittodrie has been midfielder Ryan Christie, who has signed on loan from Celtic until the end of the season. The 21-year-old has only made 13 appearances for the Parkhead side since moving there from Inverness Caledonian Thistle in 2015.

Ryan Christie came on as a substitute for Aberdeen in their 3-0 win against Dundee

Out: Midfielders Cammy Smith and Craig Storie have joined St Mirren on loan until the end of the season, while striker Lawrence Shankland has swapped a loan spell at the Buddies for one at Morton. Defenders Scott McKenna and Daniel Harvie have extended their loans at Ayr United and Dumbarton respectively. Winger James Maddison opted to stay and try and prove himself at Norwich rather than try to extend his Aberdeen stay. Forward Wes Burns returned to Bristol City after his loan stint and has subsequently signed for Fleetwood Town.

Celtic

In: Brendan Rodgers has captured Ivory Coast midfielder Eboue Kouassi for a £2.8m fee from Russian club Krasnodar, but the Celtic boss is disappointed that it seems to be the only piece of incoming activity this transfer window.

Out: Four midfielders, a defender and a goalkeeper are all involved in loan deals until the end of the season. Norwegian Kristoffer Ajer joined Kilmarnock, Ryan Christie went to Aberdeen and Leo Fasan to Port Vale. Joe Thomson has gone to get first-team football at Queen of the South and Aidan Nesbitt extended his spell at Morton. Centre-back Jamie McCart will spend the rest of the campaign at Inverness Caledonian Thistle. Defender Efe Ambrose's loan move to Blackburn Rovers is still awaiting official confirmation, while winger Michael Duffy moved to Dundalk on a permanant transfer.

Kristoffer Ajer (right) has already played twice for Kilmarnock since his recent loan move to Rugby Park

Dundee

In: Paul Hartley has moved to secure the services of former Motherwell striker Henrik Ojamaa on loan from Go Ahead Eagles. Adding another two years onto the initial short-term contract of Canadian striker Marcus Haber was another piece of Dens Park business. Former Ross County midfielder Marc Klok has signed until the end of the season after impressing on trial.

Out: Striker Rory Loy has been loaned to St Mirren for the rest of the season, forward Yordi Teijisse heads to Germans Wuppertaler and midfielder Nicky Low will experience pastures new on loan at Derry City. Defender Conor Quigley (Stirling Albion), centre-back Matty Smyth (Arbroath), midfielder Calvin Colquhoun (Stirling Albion) and forward Josh Skelly (Arbroath) are also all out on loan.

Rory Loy scored his first goal for St Mirren against Falkirk at the weekend

Hamilton Academical

In: Martin Canning has added English left-back Blair Adams to his Accies squad on a free transfer from Cambridge United - the 25-year-old has signed an 18-month deal at New Douglas Park. And Greek right-back Giannis Skondras has arrived from PAOK Salonica.

Out: Goalkeeper Robbie Thomson left for Falkirk and German left-back Lenny Sowah opted to join Hearts at the end of his short-term deal at Hamilton. Trinidadian forward Richard Roy has been released.

Heart of Midlothian

In: Head coach Ian Cathro has been busy trying to re-shape his squad. Two centre-backs have been signed, in the shape of Northern Ireland's Aaron Hughes and Greek Anastasios Avlonitis. A couple of full-backs also arrived - one is former Hamilton left-back Lenny Sowah and the other is Slovenian Andraz Struna. Greece international Alexandros Tziolis provides another option in midfield. In terms of attacking, the Jambos have brought in Stoke City's Morocco under-23 winger, Moha El Ouriachi Choulay, on loan, as well as French set-piece specialist Malaury Martin. Frenchman Dylan Bikey was snapped up after scoring nine goals in nine games for Stirling Albion, while Hearts paid Anorthosis Famagusta £170,000 for fellow striker Esmael Goncalves.

Malaury Martin scored in Hearts' Scottish Cup win against Raith Rovers

Out: A fair few departed Tynecastle in January. Striker Robbie Muirhead followed former Hearts head coach Robbie Neilson to MK Dons, while Spaniard Juanma moved to Japanese outfit V-Varen Nagasaki, Tony Watt returned to parent club Charlton Athletic and another forward - Bulgarian Nikolay Todorov - joined Livingston on loan. Defensively, Hearts lost Igor Rossi to Saudi Arabian club Al-Faisaly Harmah and Alim Ozturk made the switch to Boluspor in his native Turkey. Goalkeeper Kelby Mason (Bonnyrigg Rose), midfielder Lewis Moore (Cowdenbeath) and forwards Callumn Morrison (Stirling Albion) and Alistair Roy (Stenhousemuir) all went out on loan. Conor Sammon has been allowed to move to former club Kilmarnock on loan. Dario Zanatta has joined Queen's Park on loan on a development loan, meaning he can still play for Hearts Under-20s.

Inverness Caledonian Thistle

In: As Caley Thistle try to get themselves away from the foot of the table, boss Richie Foran has signed former Motherwell and Dundee United forward Henri Anier and another Irish striker called Dean Ebbe, who was most recently with Bluebell United in the Leinster Senior League. Northern Ireland striker Billy Mckay returns to the Highlands on loan until the end of the season. English midfielder Larnell Cole has extended his loan from Fulham until the end of the season and 19-year-old Celtic defender Jamie McCart also arrives on a loan deal.

Out: Striker Lonsana Doumbouya has scored six goals for Caley Thistle this season but is leaving the club to go abroad. Young forward Ali Sutherland has been released.

Kilmarnock

In: Lee Clark's large intake of players has continued this month. He's added English defender Karleigh Osborne from Plymouth Argyle on a two-year deal in addition to the loan signing of Kristoffer Ajer from Celtic. Elsewhere, defender Scott Boyd has made his move from Ross County permanent, and a trio of loanees arrived from one of Clark's former clubs, Newcastle United. They are goalkeeper Freddie Woodman, midfielder Sean Longstaff and forward Cal Roberts. Burnley defender Luke Hendrie extended his loan at Rugby Park until the end of the season. Hearts striker Conor Sammon has returned to the club on loan for a second spell. Forward Joshua Umerah has signed until the end of the season from Charlton Athletic.

Defender Karleigh Osborne joined Kilmarnock from Plymouth Argyle

Out: Much was made of top scorer Souleymane Coulibaly's £800,000 transfer to Egyptian club Al Ahly. Four loanees returned to their parent clubs - midfielder Charlee Adams (Birmingham City), striker Flo Bojaj (Huddersfield Town), defender Will Boyle (Huddersfield Town) and defender Jonathan Burn (Middlesbrough). Goalkeeper Devlin Mackay has joined Berwick Rangers on a development loan.

Motherwell

In: Everton goalkeeper Russell Griffiths joined the Steelmen on loan until the end of the season, as has Reading's Scotland under-21 defender, Zak Jules. Winger Elliott Frear arrives for an undisclosed fee from Forest Green Rovers, midfielder Shea Gordon switched from Sheffield United, while goalkeeper Oliver Pain is on loan from Sunderland.

Out: Former Inverness Caley Thistle goalkeeper Dean Brill departed Fir Park along with defender Louis Lang. Young forward Dylan Mackin has been loaned out to Alloa Athletic for the rest of the season, while defender Luke Watt joined East Fife and midfielder Tom Fry is on loan at Annan Athletic.

Partick Thistle

In: Former Arsenal defender Martin Keown's son, Niall Keown, has signed a loan deal at Firhill from Reading, while ex-Hearts and St Mirren goalkeeper Mark Ridgers signed a six-month contract with the Jags after a spell in the USA. Forward Jason Banton has joined on loan from Crawley Town.

This is Niall Keown, son of former Arsenal defender Martin Keown

Out: Polish top-tier club Jagiellonia Bialystok was the destination for full-back Ziggy Gordon on a permanent transfer. Alan Archibald also waved goodbye to German goalkeeper Thorsten Stuckmann and former Killie defender David Syme. Out on loan go defender Dom Docherty (Queen's Park), defender Michael McMullin (Peterhead) and midfielder David Wilson (Stranraer).

Rangers

In: Manager Mark Warburton netted a couple of midfield loan signings from the Premier League early in the window. Spanish midfielder Jon Toral arrived from Arsenal until the end of the season and the 21-year-old was joined by American Emerson Hyndman, 20, from Bournemouth on a similar deal. More recently they signed goalkeeper Jak Alnwick from Port Vale for an undisclosed fee. Defender David Bates' loan move from Raith Rovers was turned into a permanent one.

Out: Goalkeeper Matt Gilks has left to join Wigan after making five appearances this season. Midfielders Fraser Aird (Falkirk) and Tom Walsh (unattached) left Ibrox after long spells at the club. Loan deals elsewhere were arranged for midfielder Matt Crooks (Scunthorpe United), midfielder Jordan Thompson (Raith Rovers) and forward Ryan Hardie (Raith Rovers).

Emerson Hyndman scored Rangers' second in the 2-0 win against Motherwell on Saturday

Ross County

In: A flurry of new signings occurred in Dingwall. Right-back Jason Naismith joined from St Mirren and English midfielder Oscar Gobern headed for the Highlands after a spell at Mansfield Town. There were loan deals for former Motherwell midfielder Jim O'Brien, whose parent club is Shrewsbury Town, and Slovak winger Milan Lalkovic, who belongs to Portsmouth.

Out: Slovak defender Erik Cikos left the Staggies by mutual consent, as did youngster Kyle MacLeod. Defender Ross Brownlie (Elgin City), defender Chris McLaughlin (Forfar Athletic) and forward Ross MacIver (Wick Academy) have been loaned out for the rest of the season.

St Johnstone

In: Full-back Clive Smith arrived on loan from Preston North End shortly before the transfer deadline just when it looked like Saints would not sign anyone.

Out: Five youngsters have either started or extended loan deals in order to get first-team experience. They are goalkeeper Mark Hurst (East Fife), defenders Jason Kerr (East Fife), Liam Gordon (Peterhead) and Aaron Comrie (Peterhead), and winger Connor McLaren (Stirling Albion).