Updates with afternoon levels

By Ragini Mathur, Johann M Cherian and Sukriti Gupta

Aug 6 (Reuters) - Chile's peso declined the most among Latin American currencies on Wednesday, after the local central bank unveiled plans to boost international reserves, while investors were also scrutinizing U.S. tariffs on India and Brazil.

In a move that surprised investors, U.S. President Donald Trump unveiled an additional tariff on Indian goods , set to take effect 21 days after August 7. The new tariff will push duties on some Indian exports as high as 50% – among the steepest imposed on any U.S. trading partner.

Trump cited New Delhi's continued purchases of Russian oil as the reason for the sharply increased tariff rate.

Indian markets closed before the news, but a U.S.-listed iShares India ETF INDA.N slipped 0.3% to a three-month low. Depository receipts of Dr Reddy's Laboratories RDY.N REDY.NS lost 2.5% and those of Wipro WIT.N WIPR.NS and Infosys INFY.N INFY.NS dipped 1.5% and 0.9%, respectively.

On the currency front, the 1-month rupee forward INR1MNDFOR= was last flat against the dollar.

"While markets have already started pricing in the risk of a sharp tariff hike, a near-term knee-jerk reaction is inevitable — unless there's swift clarity or a breakthrough in negotiations," said Mayuresh Joshi, head of India equity research at William O'Neil.

"India's crude oil imports have remained diversified ... Russia is just one slice of our broader crude basket."

In Latin America, Brazil's real BRL= firmed 0.8% against a weaker dollar and touched a near one-month high and stocks .BVSP gained 1.1% to hit a two-week high as 50% U.S. tariffs on the country's exports took effect.

The U.S. enjoys a trade surplus with Brazil and top export items from the South American country were exempted from the duties last week. The BRICS group of countries has come under greater scrutiny in recent weeks as Trump accused them of pursuing "anti-American policies".

Brazil's President Luiz Inacio Lula da Silva told Reuters in an interview that he saw no room for direct talks with U.S. President Donald Trump, which he believes would turn into a "humiliation" for him.

Meanwhile, Chile's currency fell 0.7% after the country's central bank announced a three-year plan to boost international reserves by $18.5 billion, aiming to strengthen its holdings and reduce dependence on foreign credit lines.

Citigroup moved to "underweight" on the Chilean peso in its EM Bond Portfolio following the reserves program announcement.

Mexico's peso MXN= firmed 0.7% ahead of an interest rate decision by the domestic central bank on Thursday.

Elsewhere, Trump said his special envoy Steve Witkoff had made "great progress" in his meeting with Russian President Vladimir Putin, two days before a deadline set to impose new sanctions if no moves were made to end the conflict with Ukraine.

Crude prices slid to an eight-week low on the sanction uncertainty. The rouble RUB= had closed lower earlier on Wednesday, while international bonds in Ukraine rose broadly.

Key Latin American stock indexes and currencies:

(Reporting by Sukriti Gupta, Purvi Agarwal, Ragini Mathur and Johann M Cherian in Bengaluru; Editing by Richard Chang and Mohammed Safi Shamsi)

((Sukriti.Gupta@thomsonreuters.com))