The FTSE 100 has so far gained about 38 points to 4,492 after UK stocks rose for the fourth day in a row.
Strong performances on the FTSE 100 from insurer Prudential and recruitment firm Hays are leading the gains.
Prudential advanced 9p to 459p while Hays rose 2.5p to 123.75p after the recruitment company received a bid of £250m from buyout firm HgCapital for its DX business mail-delivery unit, according to the Sunday Times.
That said, EasyJet fell 75p to 157p despite the airline reporting that last momnth's passenger count rose to 2.09m people from 1.76m in May 2003.
But Marks & Spencer Group gained 4.25p to 361.75p after the Sunday Times also suggested Philip Green is prepared to pay £8bn in cash for the high street firm.
The FTSE 250 index is also up arind 29 points or 0.4% to 6125 points while the FTSE All-Share index has gained 0.7% to 2229.
In Asia, Tokyo's Nikkei 225 index gained 311.87 points to 11,439.92 earlier today, and Hong Kong's Hang Seng rose 306.48 points to 13,329.12.
And on Friday's Wall Street close, the Dow Jones Industrial Average index gained 46.91 points to 10,242.82 by the Friday close.
The S&P 500 index ended up 5.86 points at 1,122.50, and the Nasdaq Composite index rose 18.36 points to 1,978.62.IFAonline
Vitality at Work scheme
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Plans to double size in five years
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