Singapore has agreed to buy new military helicopters from Airbus and Boeing Co to replace its aging fleet of Super Pumas and Chinooks, the city-state’s defense ministry said on Monday.

Singapore has the largest defense budget in Southeast Asia at a time when China’s increasingly assertive actions in the disputed South China Sea spur regional nations to step up defense spending.

The defense ministry would buy H225M medium-lift helicopters from Airbus and CH-47F heavy-lift helicopters from Boeing, it said. Its current fleet is more than 20 years old.

“The H225M and CH-47F possess better lift and reach capabilities and will enable the RSAF (Republic of Singapore Air Force) to meet the Singapore Armed Forces’s lift requirements more efficiently with fewer helicopters and less manpower,” the ministry said.

The statement did not give financial details or say how many helicopters were involved. Earlier this year, sources familiar with the matter had valued a potential deal at $1 billion.

The decision on helicopters was initially delayed after the crash in April of a civilian Airbus Super Puma.