By Carla Mozee, MarketWatch

LONDON (Marketwatch) -- U.K. equities advanced Tuesday, with AstraZeneca PLC gaining on speculation that the British drug maker will receive a takeover bid, while GlaxoSmithKline PLC shares rose as the pharmaceutical heavyweight made a couple of its own deals.

U.K.'s FTSE 100 index leapt 1.1% to 6,699.85, following a four-day break in trading in observance of the Easter holiday. Last week, the index finished the holiday-shortened week higher by 1.1%.

The FTSE on Tuesday broke above "several resistance levels" including the 6,680 mark, paving the way for the benchmark index to retest an April peak of around 6,705, said Fawad Razaqzada, technical analyst at Forex.com, in a note.

The strongest price performer in Tuesday's session was AstraZeneca (AZN), with a 6.4% surge coming after a Sunday Times report that Pfizer Inc. -- the largest drug maker in the U.S. -- had approached AstraZeneca about a possible GBP60 billion ($100.78 billion) merger. Separately, the Daily Telegraph reported that AstraZeneca has hired Goldman Sachs and Morgan Stanley to advise it if Pfizer (PFE) were to again attempt to talk with the company about a takeover bid.

Meanwhile, shares of GlaxoSmithKline (GSK) tacked on 5.5% on plans by Novartis AG to buy Glaxo's oncology unit for about $14.5 billion, while Novartis sells its vaccines unit to Glaxo for $5.25 billion. Also, the companies are planning to combine their consumer divisions, which sell medication that doesn't require a prescription.

Shares of biopharmaceutical firm Shire PLC were also pulled higher, logging a gain of 5.9%. An estimated "robust" 13% earnings per-share compound annual growth rate from 2013 through 2018, "at a minimum given pipeline news and further cost control, justifies upside for the shares," said Jefferies which on Tuesday reiterated its buy rating on Shire.

But losing ground were miners, with Anglo American PLC down 0.3% following a Financial Times report that the company is getting ready to leave its platinum mines at Rustenberg in South Africa. Labor strikes that have hurt the country's platinum sector are among the factors Anglo American is assessing as it considers its future at Rustenberg, according to the report.

Platinum prices on Monday dropped 2% as a pay offer by platinum producers in South Africa fell short of union demands, which may result in a strike by workers continuing for weeks, according to Bloomberg.

Shares of Randgold Resources Ltd. were off 1.2%, Fresnillo PLC shed 0.5% and Rio Tinto Ltd. (RIO) slipped 0.2%.

Investors in the U.K. market will soon likely have another stock to watch, as Card Factory reportedly said it plans to list shares on the London Stock Exchange next month. The greetings-card specialist, which is majority owned by private equity group Charterhouse Capital Partners, could raise up $90 million from the float, according to Reuters.

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