Royal Bank of Scotland has cancelled its corporate hospitality at Wimbledon from today as it continues to deal with the IT meltdown which left thousands of customers without access to cash.

The bank, which says it is finally getting on top of the crisis, said it would be "inappropriate" to continue providing the hospitality.

It also confirmed it had cancelled a one-day golf tournament at Gleneagles in Scotland today that was due to feature golf legend Jack Nicklaus.

Sponsorship of sporting events is unaffected, a spokeswoman said.

The beleaguered bank had already hosted clients for the first two days of the Wimbledon championships and had planned to do so for the rest of the fortnight.

The move came as Bank of England governor Sir Mervyn King said bank bosses should be subject to a "detailed investigation" over the affair.

RBS successfully updated all but 1% of NatWest and RBS account balances on Monday night.

RBS Group has had less success sorting out the delays experienced by Ulster Bank customers, but it hopes to restore a full service for the start of next week.

The bank said in a statement: "Technical issues have caused considerable disruption to many of our retail and business customers, as well as customers of other banks. We have made significant progress in resolving the issues and are working around the clock to put things right for our customers.

"Under the circumstances, we felt it would be inappropriate to provide client hospitality at Wimbledon. Our people are focused on resuming normal service for our customers as soon as possible."

The bank declined to divulge how much money it had planned to spend on hospitality.

Sir Mervyn told MPs yesterday there would need to be a "detailed investigation" into what went wrong and why it had taken so long to sort the issues out.

RBS and NatWest have around 15 million accounts between them, but it is still unclear how many were affected by the disruption.

A spokesman for RBS Group said it may "never know" the exact figure as it was not possible to tell when everyone is expecting money to be paid into their account and some people may not have noticed problems.

Ulster Bank has estimated that about 100,000 of its customers have been caught up in the problems, which have meant that customers' balances have not been updating properly and their wages have not shown up in their accounts, although the money is "in the system".

The Financial Ombudsman Service (FOS) warned yesterday that it could be weeks before customers see all of the issues completely resolved.

The banking group has extended its opening hours this week as staff work "round the clock" to sort out the problems, which began after a software update last Tuesday.

People have had their house moves and holidays disrupted and a defendant in a court case had to spend the weekend in prison because the RBS computer failure prevented his bail money being transferred.

In a hearing with the Treasury Select Committee, Sir Mervyn said the Bank had been in close contact with management at RBS since the problem arose, and over the weekend.

He said the issues were technical and not a reflection of funding issues at the bank, which is 80% state-owned.