HSBC, Europe's largest bank, reported a set of financial results that beat estimates in the first half of 2017 and announced a $2 billion share buyback on the back of a growing capital base.

The bank said its pre-tax profit for the first half of 2017 came in at $10.24 billion, 5 percent higher than a year ago and beating the $9.5 billion average estimate by analysts polled by the bank. Adjusted revenue was at $26.1 billion.

"In the past 12 months we have paid more in dividends than any other European or American bank and returned $3.5 billion to shareholders through share buy-backs. We have done this while strengthening one of the most resilient capital ratios in the industry," Stuart Gulliver, HSBC group chief executive said in a statement.

The bank was widely expected to announce that it would buy back its own shares at between $1.5 billion to $4 billion in the second half of 2017, market watchers had said.

It had disappointed markets with just a $1 billion share buyback plan in the first six months of the year, after spending $2.5 billion doing so last year in a bid to wind down its cash stockpile.

"We expect a buyback of $2.5 billion to be announced for 2H17 — a lower figure would be seen as a disappointment we think," Deutsche Bank analysts wrote in a note.

Monday's announcement, the $2 billion share buyback, fell short of that mark.

HSBC's latest set of financial results and buyback plan will support the bank's share price further, said Jackson Wong, associate director at Huarong International Securities. The shares, a heavyweight on the , have risen 23 percent this year as of Friday's close.

"The price is not very cheap right now, but I think investors who have this stock should keep holding to it," he told CNBC's "Capital Connection."

Wong added that the rising interest rates environment bodes well for HSBC, which is one of the most rate-dependent banks.