BANGKOK, Nov 29 (Reuters) - Thailand's central bank left its key interest rate unchanged on Wednesday, as expected, ending a year-long tightening cycle amid a slowing economy and below-target inflation, while lowering its growth outlook.

The central bank said the current rate of 2.50% was suitable to support expansion of Southeast Asia's second-largest economy, which grew at its weakest pace this year in the third quarter.

The Bank of Thailand's (BOT) monetary policy committee voted unanimously to hold the one-day repurchase rate at 2.50%, the highest in a decade. It had hiked the rate by 200 basis points since August last year to curb inflation.

All 28 economists in a Reuters poll had predicted the BOT would hold the rate on Wednesday, with median forecasts showing no policy change until at least July 2025.

The BOT reduced its 2023 economic growth forecast 2.4% from 2.8% seen earlier, and cut its 2024 growth outlook to 3.2% from 4.4%. The economy expanded 2.6% last year.

The adjusted 2024 forecast did not factor in the impact of the government's controversial 500 billion baht ($14.3 billion) digital handout policy to be implemented next year. It said it saw growth of 3.8% next year if factoring in the signature policy.

The economy grew much less than expected at 1.5% in the July-September quarter from a year earlier on weak exports and government spending.

Last week, Prime Minister Srettha Thavisin said the economy was in "crisis", stressing the need to forge ahead with the handout policy. ($1 = 34.94 baht) (Reporting by Orathai Sriring, Kitiphong Thaichareon, Satawasin Staporncharnchai and Chayut Setboonsarng; Editing by Martin Petty)