UPDATE 3-IMF sharpens focus of forex monitoring - Rato

(Adds details from Rato interview in paragraphs 6 to 11)

By Lesley Wroughton

MONTREAL, June 18 (Reuters) - The International Monetary Fund has approved changes that sharpen its monitoring of member countries' foreign exchange policies and warns governments against using tactics that may trigger external instability, IMF chief Rodrigo Rato said on Monday.

The changes, the first in 30 years to the IMF's guidelines for monitoring currencies, provides clearer guidance to IMF staff on currency surveillance and to member countries on how they should manage their exchange rate policies.

"The new decision reflects current best practice in our work of monitoring members' exchange rate policies and domestic economic policies," Rato, the IMF's managing director, told an economic conference in Montreal.

"It reaffirms that surveillance should be focused on our core mandate, namely promoting countries' external stability," he added.

While the IMF's surveillance maintains the focus on currency manipulation and intervention in the currency markets, it now also ensure that "a member should avoid exchange rate policies that result in external instability," he said.

In an interview with Reuters, Rato said the revised guidelines were not intended to pressure any one country.

"These new rules are not designed to step up pressure," Rato said. "These rules are designed to make evenhandedness a key question and to make it transparent to us and the outside world what surveillance is about."