Arsenal are expected to complete the loan signing of Barcelona playmaker Denis Suarez on deadline day while Newcastle look set to break their record transfer fee for Miguel Almiron.
Gunners head coach Unai Emery worked with Spaniard Suarez while at Sevilla, and is keen to bring the 25-year-old to the Emirates Stadium.
On Wednesday afternoon, Barcelona confirmed on their club website that Suarez had agreed a contract extension until 2021, and revealed he would now spend the rest of the current season at Arsenal, with an option to buy.
The LaLiga leaders, though, later removed the article, with Arsenal yet to make any formal announcement.
Arsenal have also been linked with moves for Belgian winger Yannick Carrasco from Chinese club Dalian Yifang as well as Inter Milan's Croatian international Ivan Perisic.
Meanwhile, 24-year-old Paraguayan midfielder Almiron has reportedly been undergoing the final details of his transfer on Tyneside ahead of a £21million switch from Atlanta United.
West Ham are thought to be close to agreeing a deal to secure the signing of striker Maxi Gomez from Celta Vigo, with the player expected to remain at the Spanish club until the end of the season.
The Hammers did confirm one new arrival on Wednesday afternoon, with Portugal Under-20 international forward Mesaque Dju having signed from Benfica on a three-and-a-half-year contract.
Manchester United midfielder Marouane Fellaini, 31, could be on his way to the Chinese Super League, while Monaco midfielder Youri Tielemans has been linked with several Premier League sides including Leicester, Newcastle, West Ham and Arsenal.
Tottenham winger Georges-Kevin N'Koudou could be heading to the Stade Louis II on loan until the end of the season, the 23-year-old's game time having been limited so far.
Will Premier League clubs splash the cash like last year? (PA Graphics)
Spurs striker Vincent Janssen, out of favour under Mauricio Pochettino, is a potential loan target for Real Betis.
Chelsea will be hoping 18-year-old forward Callum Hudson-Odoi, who was left out of the squad to face Bournemouth on Wednesday, remains with the club amid continued reported interest from Bayern Munich.