(Reuters) - Indonesian Rio Haryanto will stay with Manor as a reserve driver after being dropped from the race seat, the Formula One team said on Thursday.

The decision came a day after the team announced that Frenchman Esteban Ocon was taking Haryanto's place from this month's Belgian Grand Prix due to contractual issues.

Manor said Haryanto, who is backed by Indonesian state oil company Pertamina but needed to raise substantial sums to retain his seat, had accepted an offer to stay as a reserve for the rest of the season.

"Rio will be available to deputize should either race driver be unable to take part in an event," the team said in a statement.

"He will also be immersed in engineering meetings and PR activities as the team continues its support for his racing ambitions."

Haryanto became Indonesia's first Formula One driver in March. He started 12 races without scoring a point.

Ocon is backed by both Mercedes and Renault, where he was a reserve F1 driver, and will partner German rookie Pascal Wehrlein at Mercedes-powered Manor.

Manor, the smallest Formula One team but 10th of 11 in the current championship standings, signed Indianapolis 500 winner Alexander Rossi of the United States as their official reserve in March.

However, he said this month that he turned down an offer to race the rest of the season with them due to his IndyCar commitments.

"My management and I are in constant communications with Manor and we knew there might be an opportunity to race for the last half of the 2016 season," he told Autosport.

"We gave it careful thought but declined the race seat due to my IndyCar contract."

(Reporting by Alan Baldwin; Editing by John O'Brien)