By Carla Mozee, MarketWatch

LONDON (MarketWatch) -- U.K. stocks tipped into the red Wednesday, backing away from an effort to reach a record high, with a downgrade of Barclays PLC weighing on the banking heavyweight's shares.

The FTSE 100 turned a point lower at 7,018.27, feeling the pinch from a pullback in energy and industrial shares, and a reversal in gains for consumer-related stocks. In the groups, oil major BP PLC fell 0.2%, Weir Group PLC lost 1.2%.

Brewer SABMiller PLC fell 1%. They had been down by as much as 1.9%, ahead of a formal announcement that H.J. Heinz Co. and Kraft Foods Group Inc. (KRFT) have agreed to merge (http://www.marketwatch.com/story/kraft-heinz-agree-to-merge-in-buffett-backed-deal-2015-03-25). The Wall Street Journal noted that there had been speculation Brazil's 3G Capital was interested in bidding for SABMiller along with Anheuser Busch InvBev , in which 3G holds a stake.

Under the planned Kraft-Heinz merger, 3G Capital and Berkshire Hathaway (BRK/A) will contribute $10 billion toward a special shareholder dividend as part of the transaction that would create the world's fifth largest food and beverage company.

Shares of Barclays PLC also weighed on the FTSE 100, falling 2% following a downgrade to hold from buy at Investec. The "valuation case is no longer overwhelming in the context of our deteriorating expectations for the scale and pace of [return on equity] recovery," wrote analyst Ian Gordon in a note.

But TUI AG shares held the top spot on the FTSE 100, jumped 3.8% as the tourism company said its winter 2014/15 season wrapped up as it had expected, with higher average-selling prices in most of its markets. It said for this summer, bookings and average-selling prices are each up 1%. The demand for its own holiday packages account for 74% of summer bookings, higher by three percentage points from the year-ago period.

The FTSE 100 on Tuesday (http://www.marketwatch.com/story/ftse-100-grips-onto-record-high-but-centrica-shares-lag-2015-03-24) had been on track to surpasses its previous record closing high of 7,037.67, but reversed course toward the end of the session and lost 0.3%.

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