By Nikhil Sharma

June 4 (Reuters) - Index tracking Latin American currencies soared to a more than one-year high on Wednesday, cashing in on a strained dollar as investors grappled with uncertainties from U.S. President Donald Trump's tariff agenda.

MSCI's index for Latin American currencies .MILA00000CUS rose 0.24% and was at its highest level in over one year.

A gauge of the region's equities .MILA00000PUS jumped 1.1% to build on its gains from the last two sessions.

The dollar index =USD slipped 0.3% following a weaker-than-expected U.S. private payrolls data against the backdrop of global trade tensions.

The day marked the deadline for countries to submit their best offers for trade deals to avoid Trump's punishing "Liberation Day" duties from taking effect in early July.

Doubled U.S. duties on steel and aluminium imports also took effect on Wednesday, applying to all trading partners except Britain, the only country so far to strike a preliminary trade agreement with the United States.

The increase also brings in a major setback for the Mexican economy, which carries out significant industrial trade with the U.S.

Mexico's Economy Minister Marcelo Ebrard on Tuesday announced plans to ask Washington to exclude Mexico from the higher metal tariffs, adding that tariffs were unfair given that the country imports more steel from the U.S. than it ships there.

Joan Domene, senior economist at Oxford Economics, noted that higher duties on steel might not be damaging, but pose a downside risk.

"And if trade relationships between the U.S. and Mexico do not get mended, we could see a permanent underperformance of Mexico compared to the rest of the region."

Mexico's peso MXN= rose 0.3% against the dollar, supported by elevated oil prices, while a similar move was also seen in the local equity index .MXX.

Data showed Mexican gross fixed investment rose 0.3% in March from the previous month.

In Brazil, real BRL= edged up 0.2% with caution after data revealed services activity contracted for the second consecutive month in May.

The currency is expected to flatten in the coming months, restrained by concerns about the country's fiscal deficit, a Reuters poll showed.

Brazil's Treasury said it will tap international markets with a new five-year dollar-denominated bond due in 2030 and reopen its 10-year benchmark, the Global 2035, launched just a few months earlier.

Sao Paulo's main stock index .BVSP was up 0.4%.

In other Latin American economies, Chile's peso CLP= rose 0.4% and its main stock index .SPIPSA jumped 1.3%, headed for its best day in three weeks.

Meanwhile, global markets pinned their hopes on a planned talk between Trump and Chinese President Xi Jinping sometime this week, as the two leaders seek to iron out simmering trade tensions.

In a social media post, Trump called Xi tough and "extremely hard to make a deal with," suggesting a tough road ahead for the heads of state to reach a mutual ground.

Elsewhere, Poland's main stock index .WIG20 rose 1.4% after the central bank decided to keep rates on hold, while adding that the current interest rate level will cool inflation to the target in the medium term.

Inflation in Poland slowed to 4.1% in May, above the central bank's inflation target range of 1.5% to 3.5%.

South Korean stocks .KS11 jumped to a ten-month high as investors cheered liberal candidate Lee Jae-myung's presidential win on the hopes that his corporate reform measures could boost the domestic stock market.

Ecuador's sovereign bonds extended their rally on Wednesday, with 2035 note EC221423852=RRPS up 1.6 cents to the dollar, on plans to tap capital markets next year.

Key Latin American stock indexes and currencies:

(Reporting by Nikhil SharmaEditing by Marguerita Choy)

((Nikhil.Sharma@thomsonreuters.com;))