Ryan Nelsen believes West Ham have issued a statement of intent by tying Winston Reid to a new deal.
Tottenham are keen for striker Shaquile Coulthirst to continue his development out on loan after his spell at Southend.
Neil Lennon believes spending £10million on new players would help to eradicate the blips his Celtic side have suffered from this season.
The Hoops have cruised towards the Clydesdale Bank Premier League title this season but have saved their best performances for Europe, where a successful Champions League campaign ended only last week when they exited at the last-16 stage to Juventus.
Lennon's side have come in for intermittent criticism this season for some sloppy domestic performances, most recently after losing their last two SPL matches to Ross County and Motherwell, even though they remain 15 points ahead of the second-placed Steelmen.
Celtic can reach 86 points but any more slips could see them win the SPL title with the lowest-ever points total, which stands at 84.
However ahead of Saturday's visit of Aberdeen in the SPL, the Parkhead manager was on the front foot.
He said: "Listen, what I need is investment. If I can get £10million to spend on new players in the summer, we will be even better.
"This club is ripe. We have really talented young players in the team.
"We haven't spent a lot of money, we have made a profit every window, we have cut the wage bill and sometimes when you have that sort of cut-back then the quality is diluted at times and that is what we are seeing at the minute.
"Now if I get the money that other Old Firm managers have had in the last 10-12 years I will easily get 100 points and we will make the last 16 on a regular basis.
"But am I going to ask Peter (Lawwell, Celtic's chief executive)for £10million or £12million?
"He will ask why, and if I say I want to get to 100 points I will get laughed out the door.
"If Peter says this is what we have to work with, then fine. I have never once banged his door down saying I want three or four million for that player and that player.
"I have prioritised other games in the last two league games.
"Against Motherwell I had my eye on the St Mirren (William Hill Scottish Cup) quarter-final which I thought was a huge game for us in the context of the season.
"Obviously the Ross County game was a few days after the last-16 game in Turin.
"What you will see this weekend is a fresh Celtic team ready to go for the title.
"We have already improved on last season on the pitch and with the success we have had in Europe we have improved off the pitch, for me that is as important as anything else."
Lennon was reluctant to get involved in Scottish football's on-going reconstruction saga but admitted his interest when asked about the idea of a Celtic colts side being entered into the Scottish Football League.
"Why not?" said the Northern Irishman.
"I think it would be good for the game but from what I gather there is not too much support for that.
"I think it was mooted maybe a year or two ago but nothing was taken on with it.
"For us, it is a good idea. Ourselves and Rangers are probably the only clubs who could afford to do that.
"Whether it would bring crowds in, give our players experience, I don't know.
"But look at what Barcelona and Real Madrid do in Spain, they (the clubs' colts sides) can't win the league but they can certainly compete in it and develop their younger players to a better level."
While happily referring to Celtic's city rivals in the context of colts teams, Lennon refused to be drawn on Hoops defender Charlie Mulgrew's admission during the week that if it was down to him, he would ideally have Rangers in the SPL.
"I told you before I am not going to answer any more questions about Rangers and the fact that you asked Charlie the question the other day - that disappointed me as well," Lennon said.
"Charlie was there to promote PFA Scotland player of the year and he ends up answering questions on Rangers.
"Now I have told you before if you want to pursue that line of questioning the press conference is over."
Lennon paid tribute to Dons manager Craig Brown who will retire as a boss at the end of the season but remain at Pittodrie as a non-executive director.
The former Hoops skipper said of the former Scotland manager: "I am very sorry to hear that. He is a great football man.
"He has helped me along the way in my career, whether it be actually managing or on coaching courses.
"He has had a wonderful career and I think he will be a big loss to the management fraternity."
Meanwhile, striker Anthony Stokes is looking to win himself a new deal in the final weeks of the season.
He said: "My contract is up at the end of the year but there is a year option on it so it is something we will discuss with the club in the coming weeks, I'm sure.
"I have spoken to the gaffer about it and it is something we will try to iron out over the next couple of weeks.
"I have said it plenty of times, I love it up here, I love playing for the club so of course I would like to stay."