The summer transfer window has now begun, with rumours and speculation continuing to swirl as Manchester United eye possible reinforcements.

The Red Devils brought in Bruno Fernandes and Odion Ighalo in the final days of the winter window but are still expected to be active in the summer as they aim to restore their former glories.

Here, Sports Mole rounds up the latest news on possible comings and goings from Old Trafford.

Thursday morning's Manchester United transfer talk news roundup:

Kalidou Koulibaly agent 'informs Napoli of Manchester United interest'

Napoli have allegedly been informed that Manchester United remain interested in signing defender Kalidou Koulibaly.

While the centre-back has previously been regarded as indispensable at Stadio San Paolo, president Aurelio De Laurentiis is now open to parting ways with the club's key asset.

Keen to strengthen their backline before the end of the transfer window, Manchester City boss Pep Guardiola wants to bring the 29-year-old to the Etihad Stadium.

However, according to Il Mattino, Fali Ramadani has told Napoli that United are interested in negotiating a deal for the player.

Despite previously being valued in the region of £80m, the Serie A outfit may be prepared to cash in for a fee around the £60m mark.

Koulibaly still has three years remaining on his contract.

Lionel Messi 'agrees £623m deal with City Football Group'

Lionel Messi has reportedly agreed a staggering €700m (£623m) deal with City Football Group as the Argentine prepares to leave Barcelona.

The forward recently told Barca that he wants to leave the Catalan giants during this summer's transfer window, and the South American's father and agent Jorge Messi has flown to Spain for talks.

Manchester City have emerged as the favourites for the 33-year-old despite suggestions that Chelsea, Manchester United, Paris Saint-Germain and Inter Milan were also interested.

According to the Daily Record, Messi has agreed a five-year deal with the City Football Group which will see him represent City before eventually joining MLS outfit New York City FC.

The report claims that the attacker is likely to spend three seasons with the Citizens before moving to North America, although there is 'a degree of flexibility' in the deal.

Messi was not present during Barca's pre-season training session on Monday, while he also did not turn up for a coronavirus screening on Sunday as he looks for an exit.

The four-time Champions League winner has a contract at Camp Nou until next June, but he is attempting to leave on a free transfer despite a clause allowing him to depart for nothing this summer expiring in June.

More transfer news from Manchester United:

Manchester United 'line up Milan Skriniar as Dayot Upamecano alternative'
Manchester United make contact with Inter Milan to discuss a potential deal for Milan Skriniar, according to a report. Read more.

Leeds United considering move for Manchester United defender Axel Tuanzebe?
Leeds United are reportedly contemplating whether to launch a bid for Manchester United defender Axel Tuanzebe before the end of the summer transfer window. Read more.

Dean Henderson 'to go head-to-head with David de Gea next season'
Dean Henderson will battle David de Gea for the number one goalkeeping spot at Manchester United next season, according to a report. Read more.

Manchester United 'consider putting Dayot Upamecano move on hold for a year'
Members of the Manchester United board are reportedly in favour of postponing their planned move for RB Leipzig centre-back Dayot Upamecano until next summer. Read more.

Dayot Upamecano confirms talks with clubs amid Manchester United speculation
RB Leipzig centre-back Dayot Upamecano reveals that he has held talks with clubs concerning a potential summer move. Read more.

Roma 'eyeing summer move for Manchester United's Fred'
Roma want to sign Manchester United midfielder Fred on loan this summer, according to a report. Read more.

Manchester United confirm Donny van de Beek signing
Manchester United confirm the signing of midfielder Donny van de Beek from Ajax on a five-year deal with the option of a further year. Read more.

Manchester United 'will not give up on Jadon Sancho'
Manchester United will reportedly not give up on Jadon Sancho unless the Borussia Dortmund attacker makes a statement on his future. Read more.

Man United 'make contact with Liverpool-linked Thiago Alcantara'
Manchester United contact Thiago Alcantara's advisors to discuss a deal for the Bayern Munich midfielder, according to a report. Read more.

Agent: 'Manchester United beat Real Madrid, Barcelona, Arsenal to Donny van de Beek'
The agent of Donny van de Beek says that Manchester United beat five other clubs to the signing of his client. Read more.