TOKYO (Reuters) - Japan's Seven & i Holdings ( SVNDF ), operator of the 7-Eleven convenience store chain, reported on Thursday a drop of 24% in quarterly operating profit, missing analysts' estimates.

Profit fell to 128 billion yen ($809.41 million) in the period from September to November versus 169 billion in the corresponding period a year earlier.

The results compared to an average profit estimate of 138 billion yen from seven analysts polled by LSEG.

The poor showing adds to pressure on the sprawling retailer to demonstrate it can improve corporate value as it fends off a proposed $47-billion buyout offer from Canada's Alimentation Couche-Tard ( ANCTF ) .

The firm has hastened plans to focus on its core convenience store business by offloading its range of non-core assets, among them several supermarket chains and specialist retailers.

However, operating profit dropped at its domestic and overseas convenience store arms as inflation weighs on consumer spending in Japan and North America, the group's two largest markets.

Seven & i ( SVNDF ) retained its profit forecast of 403 billion yen (USD) in the year to the end of February, lowered from last October's 545 billion yen, as reduced consumer spending due to inflation in North America hit convenience store operations there.

($1=158.1400 yen)