The prospect of a supermarket mega-merger helped carry the London stock market higher on Monday, while Wall Street rose despite investors spurning the announcement of plans by T-Mobile and Sprint to unite.
Earlier, Hong Kong led a rally across most Asian markets as traders brushed off a slowdown in the US economy, while the boost from last week's historic North-South Korea summit continued to support Seoul and the won.
"A genuinely game-changing deal in the supermarket sector was the main highlight" for London's benchmark FTSE 100 index, said Spreadex analyst Connor Campbell.
Britain's second and third biggest supermarket chains Sainsbury's and Walmart-owned Asda have agreed to merge, the pair said Monday, hoping to create a £13-billion ($18-billion, 15-billion-euro) retail king and leapfrog UK number one Tesco.
Sainsbury's stock shot up 14.5 percent to 309.00 pence, while Tesco slid 0.9 percent to 235.90 pence. Asda is not listed.
Walmart shares rose 2.3 percent in New York to $89.32.
"The reduced competition, pricing advantage from greater market share, the large 'cost synergies' and cash from property sales all make this deal attractive for shareholders," said market analyst Jasper Lawler at London Capital Group.
But shares in T-Mobile and Sprint tumbled as investors worried about the chances of US regulators allowing the number of national network operators to drop to three.
T-Mobile shares fell 6.0 percent to $60.63 while Sprint shares tanked 13.4 percent to $5.63.
A previous effort by the firms to merge in 2014 was abandoned after the Obama administration signaled it was unlikely to approve.
Meanwhile Marathon Petroleum announced that it will acquire Andeavor for $23.3 billion to form the largest oil refining company in the United States by capacity.
Shares of Andeavor surged 14.6 percent to $110.40 in midday trading, while Maratahon slumped 5.5 percent $76.92.
In Asia Hong Kong ended 1.7-percent higher, with a better-than-forecast Chinese factory activity reading also providing support as it eased concerns about a slowdown in the mainland economy.
South Korean traders remain upbeat after Friday's meeting between President Moon Jae-in and Kim Jong Un, which fuelled hopes for peace on the peninsula and for Pyongyang's possible denuclearisation. Seoul finished 0.9 percent higher.
Sydney gained 0.5 percent, while Tokyo and Shanghai were closed for public holidays.
Attention this week turns to the Federal Reserve's latest policy meeting. While the Fed is not expected to raise borrowing costs, its statement Wednesday will be scanned for clues about future moves.
"There is some caution ahead of the decision on US interest rates and potentially make-or-break earnings from Apple" on Tuesday, said London Capital Group's Lawler.
Apple shares have slid in the past couple of weeks on concerns about slowing phone sales.
Lawler said extra volatility in the bond market has put more emphasis on economic data, with attention focused on the US jobs report and GDP data from the eurozone on Friday.
New York - Dow: UP 0.6 percent at 24,448.97 points
London - FTSE 100: UP 0.9 percent at 7,509.30 (close)
Frankfurt - DAX 30: UP 0.3 percent at 12,612.11 (close)
Paris - CAC 40: UP 0.7 percent at 5,520.50 (close)
EURO STOXX 50: UP 0.4 percent at 3,534.19
Hong Kong - Hang Seng: UP 1.7 percent at 30,808.45 (close)
Seoul - Kospi: UP 0.9 percent at 2,515.38 (close)
Tokyo - Nikkei 225: Closed for a public holiday
Shanghai - Composite: Closed for a public holiday
Euro/dollar: DOWN at $1.2074 from $1.2125 at 2100 GMT on Friday
Pound/dollar: DOWN at $1.3759 from $1.3778
Dollar/yen: UP at 109.38 yen from 109.13
Oil - Brent North Sea: UP 18 cents at $74.82 per barrel
Oil - West Texas Intermediate: DOWN 11 cents at $68.21
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