Colombia's central bank announced late on Friday it will auction $500 million in dollar call options whenever the currency falls 3 percent from its 20-day moving average, down from the previous 5 percent trigger.
Analysts cheered the bank's willingness to act but said that intervention should be rare. They noted that the peso has rarely moved by 3 percent from its 20-day moving average in recent months. So far, the mechanism has never been activated.
On Friday, the central bank also raised its benchmark rate by 25 basis points, to 6.25 percent, and kept the door open for further tightening as had been expected.
The moves echoed measures adopted by Mexico's government last week, including dollar sales in the spot market, budget cuts and an unexpected rate hike.
J.P. Morgan analyst Ben Ramsey said in a client note he expects Colombia's central bank to increase its benchmark rate again by 25 basis points in March and April, which would allow it to cut rates by 125 basis points between September 2016 and January 2017.
The Mexican and Colombian pesos have been hard hit by slumping oil prices, which have weighed on trade and tax revenue and pressured inflation expectations.
A recovery in crude prices on Monday helped rekindle demand for emerging-market assets, after the world's oil consumer body said it expected US shale production to fall this year and in 2017.
Also helping sentiment was a Chinese stock rally following the announcement that the country had decided to replace its top securities regulator. The move followed comments by senior policymakers signaling China could bolster its efforts to stave off financial turmoil.
Global risk appetite lifted the Brazilian real beyond 4 to the US dollar as it continued to outperform its peers. A drop of more than 30 percent in the real last year has helped Brazil's current account recover more quickly than expected, despite political turmoil and a deep recession.