San Francisco Frontiers - Stocks extend Wall St gains, 7-Eleven owner plunges

Investors have walked a cautious line this week as they ascertain the trade outlook after the US president unveiled a flurry of fresh tariff threats, with the latest being letters to scores of countries notifying them of levies of up to 15 percent.

Meanwhile, Tokyo-listed shares in the Japanese owner of 7-Eleven plunged after its Canadian rival pulled out of an almost $50 billion takeover bid, ending a long-running battle over the convenience store giant.

All three main indexes in New York ended in the green on Wednesday, with the Nasdaq at another record, following a brief sell-off that came after it emerged Trump had raised the idea of firing Fed boss Jerome Powell in a closed-door session with lawmakers.

The markets soon bounced back after Trump denied he was planning to do so, saying: "I don't rule out anything, but I think it's highly unlikely."

The news caused a spike in US Treasury yields amid fears over the central bank's independence and came after the president spent months lambasting Powell for not cutting interest rates, calling him a "numbskull" and "moron".

"This Trump vs Powell saga is obviously important to market sentiment, and it seems fair to think Trump's series of social posts was strategically designed to gauge the reaction in markets -- a trial balloon if you will," said Chris Weston, head of research at Pepperstone.

"It seems that Trump indeed got his answers, and while (economic adviser) Kevin Hassett or any of the other names on the billing would be highly capable, the market has shown that it will take its pound of flesh if indeed Powell's dismissal were to become a reality."

The Fed issue came as investors were already digesting a series of trade war salvos from Trump in recent weeks that saw him threaten Brazil, Mexico and the European Union with elevated tariffs if they do not reach deals before August 1.

He also flagged hefty levies on copper, semiconductors and pharmaceuticals, and while he reached an agreement with Indonesia on Tuesday, there are around two dozen more still unfinished.

On Wednesday, Trump said he would send letters to more than 150 countries outlining what tolls they would face.

"We'll have well over 150 countries that we're just going to send a notice of payment out, and the notice of payment is going to say what the tariff" will be, he told reporters, adding they were "not big countries, and they don't do that much business".

He later told the Real America's Voice broadcast that the rate would "be probably 10 or 15 percent, we haven't decided yet".

Meanwhile, the Fed's "Beige Book" survey of economic conditions pointed to increasing impacts from the tariffs, with many warning they passed along "at least a portion of cost increases" to consumers and expected costs to remain elevated.

Asian markets opened on a wary note but most managed to take up Wall Street's lead as the day wore on.

Shanghai, Sydney, Seoul, Singapore, Taipei, Bangkok, Wellington and Jakarta all rose, as did London, Paris and Frankfurt.

There were losses in Hong Kong, Mumbai and Manila.

Tokyo's rise was overshadowed by 7-Eleven owner Seven & i Holdings plunging more than nine percent after Canada's Alimentation Couche-Tard withdrew its $47 billion offer for the firm.

ACT released a letter sent to Seven & i's board, accusing it of "a calculated campaign of obfuscation and delay".

The decision ends a months-long saga that would have seen the biggest foreign buyout of a Japanese company, merging the 7-Eleven, Circle K and other franchises to create a global convenience store behemoth.

- Key figures at around 0810 GMT -

Tokyo - Nikkei 225: UP 0.6 percent at 39,901.19 (close)

Hong Kong - Hang Seng Index: DOWN 0.1 percent at 24,498.95 (close)

Shanghai - Composite: UP 0.4 percent at 3,516.83 (close)

London - FTSE 100: UP 0.4 percent at 8,959.71

Euro/dollar: DOWN at $1.1591 from $1.1641 on Wednesday

Pound/dollar: DOWN at $1.3385 from $1.3414

Dollar/yen: UP at 148.74 yen from 147.80 yen

Euro/pound: DOWN at 86.59 pence from 86.72 pence

West Texas Intermediate: FLAT at $66.39 per barrel

Brent North Sea Crude: DOWN 0.1 percent at $68.47 per barrel

New York - Dow: UP 0.5 percent at 44,254.78 (close)

C.Diaz--SFF