SINGAPORE -- Asian currencies, led by the Philippine peso, mostly firmed on Monday off the back of oil's recent slide, but investors were cautious ahead of US bank results this week that will provide another gauge on the health of the financial sector.

Benchmark US crude hovered around $130 per barrel Monday after dropping more than $15 in the last week, helped push the Philippine peso to a one-month high in morning trade.

The currency rose 0.3 percent to P44.30 per dollar and was also still riding the bullish sentiment generated by a 50-basis-point hike in interest rates last Thursday.

"The peso remains stronger, and was definitely helped by the rate hike last week, plus oil prices are dropping," a trader in Manila said.

Another Manila-based trader said the rate hike had affirmed the stronger Philippine currency.

Analysts at JPMorgan said a stronger peso would be consistent with the agenda of the country's central bank to curb inflation, but it warned of possible downside for the currency.

"Volatile risk appetite and oil prices remain risks," they said in a research note.

The Thai baht also strengthened on Monday to its highest in a month following the Bank of Thailand's decision last week to increase interest rates by 25 basis points, marking its first rate rise in two years.

The baht inched up by 0.1 percent to 33.28 against the dollar, its highest since June 19.

Apart from oil, Asian investors were focused on earnings reports from several major US banks due this week, including Regions Financial Corp, Fifth Third Bancorp and Washington Mutual.

The US dollar was marginally weaker against a basket of currencies as investors held back ahead of these reports but the currency held on to most of last week's gains following improved sentiment on the US financial system.

The Malaysian ringgit, which had lost 0.6 percent in the previous four sessions as domestic political burdens weighed on the currency, crawled up by 0.1 percent to 3.235.

However, economists said any rebound by the ringgit may be short-lived as political uncertainty continues to pressure domestic markets.

The ruling party is under pressure from a strengthened opposition. At the same time, popular Malaysian opposition figure Anwar Ibrahim faces sodomy charges, which he says were trumped up in a high-level conspiracy to quash the opposition's rise.