Stocks pared strong early gains ahead of a raft of US economic data scheduled for release in the afternoon amid continued worries over the situation in Greece.As of 08:56 the FTSE 100 was higher by 24.21 points to 7,008.64.The top flight index snapped higher at the start of the session following the release of somewhat better than expected readings on China's manufacturing sector.The 'official' Chinese manufacturing sector purchasing managers' index increased to a reading of 50.2 from 50.1 in April, as expected. A similar survey from HSBC rose to 49.2, from 48.9 in the month before (consensus: 49.2).Julian Evans Pritchard at Capital Economics pointed out how both indices showed a rise in the employment and new orders components."Overall, today's PMI readings add weight to our view that the economy is finally turning a corner. With more policy support likely in coming months we are optimistic that growth will begin to pick-up, at least over the short-run."A raft of economic data was scheduled for release later in the day Stateside. That included data on personal income and spending and the latest reading on the state of US manufacturing, courtesy of the ISM institute.Acting as a backdrop, investors were awaiting the latest US non-farm payrolls data due out on Friday, which were expected to be key in shaping expectations for Fed rate hikes this year.The outlook for Greece darkened on Sunday after the country's prime minister, Alexis Tsipras, accused bailout monitors of seeking to impose "harsh punishment" on Athens. That came as a €300m payment to the IMF, due on Friday, loomed closer.Drug giants announce latest cancer breakthroughsShares in AstraZeneca rose 2.5% on Monday following positive takeaways from the annual meeting of the American Society of Clinical Oncology, during which the company presented preliminary data for one of its lung cancer drugs.UK Financial Investments, the state investment vehicle, has lowered its stake in Lloyds to 18.99% from the 19.93% it held on 12 May. That comes on the heels of continued market speculation regarding a sale of shares to the public with the aim of returning the lender wholly to private ownership - possibly as early as September.Investment bank Stifel Financial Corp is reportedly in advanced talks to acquire Barclays' US wealth management unit in a deal that could come as early as next week.Playtech has signed a deal to acquire Plus 500 at 400p per share in move described by the company as "transformational". The acquisition will be immediately enhancing.Defence and aerospace group Ultra Electronics Holdings has reached a deal to acquire the electronics products division of Kratos Defense and Security Solutions for $265m (£173.5m).Bank of Georgia's healthcare subsidiary has agreed to acquire 50% of GNCo, which owns the largest hospital in Georgia. The move, which increases its number of beds in Georgia to 2,670, is part of the company's plan to expand its healthcare services business through such acquisitions, which are focused on the Tbilisi region.