LONDON (Reuters) - A win for Donald Trump in the U.S. presidential election in November would herald a spike in long-term U.S. Treasury yields, said Edmond de Rothschild Asset Management's Chief Investment Officer Benjamin Melman on Thursday.

Trump's approach on taxes and immigration would put pressure on the U.S. labour market and wider economy, Melman told a press conference on the firm's H2 outlook.

Trump has established a sizable lead over President Joe Biden in the White House race since the two candidates debated on June 27.

Ten-year U.S. Treasury yields rose to more than three-week highs after that debate, near 4.5% in a move some analysts say reflects growing market expectations for a Trump win.

"What is true about Donald Trump, his programme, is significantly inflationary," said Melman.

"Even if the environment is bullish in fixed income...the long end of the U.S. yield curve is less bullish in our view due to the U.S. political risk premium."

Trump has pledged to impose tariffs on foreign imports, and up to at least 60% on Chinese goods coming into the U.S., which if passed on to U.S. consumers in the form of price hikes would fuel inflation.

Trump also has plans to launch the largest deportation effort in U.S. history, focusing on criminals but aiming to send millions back to their home countries.

"When the odds of Trump being elected got higher suddenly, the risk pricing from the markets was immediate," Jacques Aurelien Marcireau, co-head of equities at of Edmond de Rothschild, told the press conference.

Edmond de Rothschild has recently grown more cautious about European assets, until the French political landscape becomes more settled.

Their bond market positions include carry strategies profiting from rate differentials between asset values and corporate and financial hybrid debt which bear characteristics of both stocks and bonds.