LONDON -- The FTSE 100 (INDEX: ^FTSE) has had a cracking start to the New Year, soaring over the 6,000 level and closing on a new 52-week high of 6,122 points on Friday. The index of top U.K. stocks has been boosted by the U.S. fiscal cliff deal, the lack of change to U.K. and European interest rates, a new fiscal stimulus in Japan, and some promising early news on the U.K.'s Christmas trading season. Here are some stocks that have been moving strongly this week.

Barclays (BARC 6.36%)
The pariah status of Britain's banks seems to be well past, and they have started the year well. Barclays has continued its storming rise, putting on another 23 pence (8.3%) this week to hit a 52-week record of 300 pence on Friday. The price has doubled since its 2012 low point in July, and those who bought when the price really hit the depths in 2009, at just 50 pence, have done very nicely for themselves.

Schroders (SDR -5.39%)
The rest of the financial sector is off to a strong start to the year, too, with asset manager Schroders gaining a further 17 pence to 1,819 pence, to take its gain since the start of January to 8%. And that's another 52-week high, up 56% since the 1,163 pence low the stock hit in May 2012. Schroders is currently managing more than 200 million pounds in funds and is doing well even in today's harsh investment climate.

ARM Holdings (ARM)
ARM Holdings, whose chip designs are to be found in iPhones and all manner of other mobile computing devices, started 2013 even more strongly than it ended 2012, with the price spiking up another 68 pence (8.5%) this week to 870 pence. That takes it up 13% since the start of the year, and up 50% over the past 12 months. That's pretty good going for a highly valued growth stock that's trading on a P/E of 60 based on 2012 earnings expectations.

Tullow Oil (TLW 1.00%)
The price of Tullow Oil has been falling of late, and it dropped another 89 pence (7%) to 1,186 pence, after the company released its 2012 trading update. Revenue for the year should be around $2.35 billion, which is a little up on 2011. Debt stands at around $1 billion, with Tullow's capital expenditure for this year expected to reach $2 billion as it plans to drill 40 new wells. An earlier announcement of a plan to sell off North Sea assets was seen as a shift to a higher risk strategy and led to a falling price.

What now?
As usual, this week's FTSE trading provided some large share-price movements -- and perhaps some buying opportunities. Indeed, legendary investor Warren Buffett has spent more than $1 billion buying the shares of one of the U.K.'s most successful FTSE large caps.

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