Barclays Plc shareholders are expected to comfortably approve the British bank's sale of asset manager Barclays Global Investors to BlackRock when they vote on the $13.5 billion deal on Thursday.

The bank will also face protests from staff outside the meeting about its plan to close its final salary pension scheme for British staff in favour of a cheaper arrangement, however. Union Unite said staff were incensed at the move and could strike.

Shareholders must recognise that the possibility of strike action will be very damaging for the bank, said Keith Brookes, Unite national secretary.

Barclays agreed in June to sell BGI in a cash and shares deal to remove concerns about its capital strength and give the UK bank a near 20 percent stake in the enlarged BlackRock (BLK.N), which will become the world's largest money manager.

Approval of the deal should sail through at a meeting starting at 1000 GMT, according to analysts and industry observers.

Barclays, which has raised funds privately and avoided selling a stake to the UK government, said earlier this week the sale of BGI is on track to complete in the fourth quarter.

The deal will lift its core Tier 1 capital ratio by about 1.5 percentage points to 8.8 percent.

BlackRock will be the biggest single client of Barclays Capital after the deal, BarCap Chief Executive Bob Diamond said.

The asset manager, which will be renamed BlackRock Global Investors, will double in size to about $2.8 trillion of assets under management and through iShares will get exposure to exchange-traded funds, one of the fastest growing areas in the industry.

(Reporting by Steve Slater; editing by Simon Jessop)