Updates with mid-session prices

By Nikhil Sharma and Purvi Agarwal

May 20 (Reuters) - Most Latin American stocks and currencies took a breather on Tuesday after strong gains in the previous session, while some lingering caution over the U.S. growth outlook weighed on broader sentiment.

MSCI's index of Latam currencies .MILA00000CUS was down 0.1%, as most currencies slipped against the greenback.

Chile's peso CLP= fell 0.7%, the most among peers, tracking lower copper prices. MET/L

Brazil's real BRL= followed with a 0.4% loss. The world's largest chicken exporter has been pressured since the first commercial-farm outbreak of bird flu was confirmed last week, prompting trade embargos from major importers.

Colombia's peso COP= was flat, despite a top Moody's analyst warning the country could face a ratings downgrade if it fails to stabilize public debt and comply with the fiscal rule.

Global markets appeared to pause after a volatile session triggered by Moody's downgrading the U.S. sovereign credit rating, citing deficit concerns. The rating cut came at a time when a sweeping tax-cut bill is headed for a vote in the House of Representatives later this week.

The dollar index =USD was down 0.4% on the day, continuing its selloff from Monday, while Wall Street's main indexes also fell. USD/ .N

"With conviction growing that the dollar has put in an important top, emerging market currencies around the world are catching a bid," said analysts at ING.

"The greenback should weaken for the remainder of the year and investors should use temporary dollar strength to reduce or hedge their exposure," said Mark Haefele, chief investment officer at UBS Global Wealth Management.

The Peruvian sol PEN= and the Mexican peso MXN=, however, capitalized on the dollar weakness to gain 0.1% and 0.2% respectively, with the latter at an over seven-month high.

Equities in the region did not do better, as the index tracking them .MILA00000PUS fell 0.2% after advancing over 1% on Monday.

Declines in heavyweight Brazilian .BVSP and Mexican .MXX stocks outweighed gains in Argentina .MERV and Colombia .COLCAP.

Elsewhere, the Romanian leu EURRON= was down 0.5% against the euro, relinquishing most of the gains it clawed back after Sunday's surprise presidential election victory of centrist Nicusor Dan over a hard-right rival.

Its central bank held out the prospect of policy easing later this year if markets recover from recent election-induced turmoil.

Nigeria's central bank kept rates on hold for the second time in a row, amid improving macroeconomic indicators.

Ukraine's international bonds slipped, with the 2035 maturity bond XS2895057177=TE sliding more than one cent against the dollar, as investors weighed the possibility of an end to a three-year-old Russian war in Ukraine.

U.S. President Donald Trump said after his planned call with Russian President Vladimir Putin that Moscow has agreed to immediately start negotiations for a ceasefire. However, the Kremlin said Trump and Putin did not discuss a timeline for a ceasefire.

Key Latin American stock indexes and currencies:

(Reporting by Nikhil Sharma and Purvi Agarwal; Editing by Alexandra Hudson and Vijay Kishore)

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