Everton striker Lukaku is expected to officially join the Red Devils after Everton accept record offer.
Klaassen, 24, became Everton's second summer signing last month for around €27m (£23.6m, $30.8m).
Antonio Conte "fuming" after losing out on Belgium international to Manchester United.
L'Equipe report the Gunners have returned with a second offer for the France star.
Arsenal are still interested in Lemar and Mahrez and would need to offload a foreign player.
The Italy international is Ernesto Valverde's preferred midfield target this summer.
Phil Neville believes Lukaku is a different type of striker from what United have had for a long time.
United have agreed a £75m fee with Everton for the transfer of Lukaku.
Sanchez believed to be seeking contract worth £400,000-a-week.
Los Blancos have also signed Theo Hernandez from Atletico Madrid to replace Fabio Coentrao.
Everton looking to offset impending Romelu Lukaku departure.
Merseysiders are under no pressure to sell and say reports that a bid has been accepted are "premature".
Former Real Madrid legend had been linked with a free-agent move to Anfield.
Everton also beat off interest from Arsenal and West Ham United to sign the Nigerian.
Charlie Nicholas says a potential £50m deal is too much for the Gunners to overlook.
Mane absent for domestic friendlies against Tranmere Rovers and Wigan Athletic after knee surgery.
Wayne Rooney and Alvaro Morata's future could be affected by Lukaku's move to Old Trafford.
But Uruguay international admits he would stay at the Atletico if club give him a lifetime contract.
Chalobah, 22, spent the 2012/13 season on loan at Vicarage Road.
Ernesto Valverde considers the Spaniard a crucial player ahead of the coming season.
Lukaku seemingly preferred a move to Chelsea.
The Chilean's contract expires in the summer of 2018.
Nigel Winterburn believes the London Stadium could offer both players a possible exit route.
United manager Jose Mourinho has maintained regular contact with Morata.
AS claim Manchester United and PSG are also keen on the Colombian international.
Lacazette has become Arsenal's second signing of the summer.
The Belgium international is wanted by Chelsea manager Antonio Conte.
Kante has won the Premier League twice with Leicester and Chelsea.
Shaw has been out of action with an ankle ligament injury since April.
The Colombian international signed with Juventus on a permanent deal in May.