Last week, a spokesman for the batsman said he had been suspended following an "off-field incident".

Hales, 30, was part of a provisional 15-man squad named for the World Cup.

A statement from Hales' management company said the decision has left him "devastated".

ECB chief Ashley Giles said: "I want to make it clear this is not the end of Alex's career as an England player."

The ECB has refused to say what Hales has done to warrant his withdrawal, citing confidentiality concerns.

Hales missed Nottinghamshire's One-Day Cup games last week for what the county described as "personal reasons".

The incident happened last year, and the player's spokesman added: "While the issue is not cricket-related, he accepted it was right he was suspended."

The ECB says he has also been removed from the England squad for the one-day international against Ireland on Friday, as well as the Twenty20 international and ODI series against Pakistan.

A replacement for the World Cup squad must be named by 23 May, when final squads are submitted to the International Cricket Council.

"We have thought long and hard about this decision," added Giles, the ECB's managing director of England men's cricket.

"We have worked hard to create the right environment around the England team and need to consider what is in the best interests of the team, to ensure they are free from any distractions and able to focus on being successful on the pitch.

"The ECB and the PCA (Professional Cricketers' Association) will continue to aid Alex and work alongside his county club Nottinghamshire to give him the support he needs, to help him fulfil his potential as a professional cricketer."

Hales' management company said in a statement it is "hugely disappointed at the treatment" of the cricketer.

It said the ECB "insisted on Alex taking certain rehabilitation measures following his suspension" and that, "at every stage, Alex fulfilled his obligations and both he and his representatives were given assurances that any suspension - again under the ECB's guidelines - could not affect his selection for the World Cup".

The statement added: "The fact all those assurances seem to have been rendered meaningless has understandably left Alex devastated. He will take time to reflect on both his actions and the subsequent decisions, but will receive the support from his team he deserves."

Hales has played 11 Tests, 70 one-day internationals and 60 T20 matches for England.

He is now regarded as a white-ball specialist, however, and in 2018 signed a new contract with Nottinghamshire to play only limited-overs matches until the end of the 2019 season.

It is the second time he has been suspended, following his punishment - which also included a fine - for an incident outside a Bristol nightclub in September 2017.

The England limited-overs batsman did not face any criminal charges, while team-mate Ben Stokes was cleared of affray at a trial.

In addition to the incident in Bristol, Hales was charged in relation to "inappropriate images".

Speaking to the Guardian earlier this month, the batsman said the fallout from the incident had been a "lesson learned the incredibly hard way", and subsequently told BBC Sport he believed he deserved a "second chance" after he and his team-mates were "caught up in the wrong place at the wrong time".