BANGKOK, Thailand - The Thai budget airliner One-Two-Go, which suffered a deadly crash last year, will be forced to suspend the bulk of its operations starting Tuesday, the Thailand's Civil Aviation Department said.

Chaisak Angkasuwan, director of Thailand's Civil Aviation Department, said Monday that eight out of twelve planes operated by One-Two-Go Airlines will be suspended for 30 days.

"We found that their system to ensure aviation safety is not up to standard," Chaisak said in a telephone interview. "Their pilot screening is also not systematic and not up to standard."

The eight planes suspended are all MD-82, he said, adding that the airline's remaining four jets would not be grounded.

Airlines officials could not be reached for comment.

The partial suspension coincides with the company's decision Friday to cease operations temporarily starting Tuesday for financial restructuring. It cited the rising cost of oil, increased competition and a drop in domestic traffic for its suspension.

The airline has struggled to recover from a crash in September on the tourist island of Phuket that killed 89 people. The plane skidded off a runway while landing in strong wind and rain and then it caught fire. Pilot error was the cause of the accident, Chaisak told The Bangkok Post on Monday.

The dead came from at least 10 countries, including the United States, Australia, Britain, France, Germany, Iran, Ireland, Israel, Sweden and Thailand. Official tallies confirm that Thailand had the most victims — 36 — followed by Iran with 18.