(Fixes headline tag)
* Full cabinet announcement expected on Wednesday morning
* Opposition leader Prabowo to help in defence area in cabinet
* Billionaire businessman Erick Thohir also tapped
* Some candidates who visited palace from private sector
By Maikel Jefriando and Agustinus Beo Da Costa
JAKARTA, Oct 21 (Reuters) - Indonesian President Joko Widodo asked opposition leader Prabowo Subianto on Monday to join his new cabinet for a second term, while the co-founder of tech start-up Gojek and a former chairman of Inter Milan soccer club were also tapped for posts.
Bringing on board Prabowo, who was Widodo's challenger in April's bitterly fought election, means the president can further strengthen his grip on parliament as he seeks to push through his reform agenda. The retired general's Gerindra party has the third most seats in the lower house.
The make-up of the cabinet was being closely watched to see how many technocrats - who are more likely to fall in with Widodo's plans for boosting growth and investment - were included.
Widodo had been expected to announce his full cabinet line-up on Monday, but this had been delayed until Wednesday, officials said.
"I want appointed ministers to be figures who are innovative, productive, as well as be hard and fast workers. Figures who are not stuck in monotonous routines," Widodo said in a Twitter message.
A series of candidates visiting the presidential palace on Monday said Widodo had asked them to join the cabinet, but they declined to confirm the positions offered.
Prabowo, 68, said after meeting the president he had been asked to help in the defence sector. Media reports have suggested he would serve as defence minister.
His cabinet inclusion comes after he had initially refused to concede defeat in April's vote, going to the constitutional court citing systematic fraud and abuse of power.
But after the court ruled against him the former special forces commander met Widodo on a number of occasions, including during a well-publicised ride on Jakarta's new subway system.
Indonesian political parties tend to be divided more by the rival personalities at the helm rather than ideology, meaning they can more easily switch allegiances to get into power.
Nadiem Makarim, 35, the chief executive of Indonesian ride-hailing and payments firm Gojek, was another visitor at the palace.
"I have received a big honour to be able to join the cabinet of the president," Makarim told reporters.
He has been linked to a possible post in a new digital economy ministry or in education. Gojek said the company's president Andre Soelistyo and its co-founder Kevin Aluwi would take over the leadership of the $10 billion unicorn.
Widodo's election campaign manager Erick Thohir, 49, the chairman of media business Mahaka Media was also interviewed for a post, sending shares in his company up 19%.
Thohir, a former chairman of Italian soccer club Inter Milan who also has stakes in basketball teams, successfully led the team organising the Asian Games hosted by Indonesia last year.
The billionaire businessman said he would step down from his company if appointed, noting the president had asked candidates to sign "an integrity pact" to avoid conflict of interests.
Widodo has been besieged by "extremely intense" jockeying for posts as he sought to build a cabinet of technocrat ministers, a presidential adviser has said, declining to be named.
While analysts welcomed some of the private sector picks, Arya Fernandes at the Jakarta-based Center for Strategic and International Studies cautioned that too many political appointments could undermine the cabinet's effectiveness.
On Sunday, Widodo said around 16 ministers in the new cabinet would come from parties out of an anticipated 34 posts.
Widodo, 58, has pledged to cut red tape and keep building infrastructure to underpin growth in Southeast Asia's largest economy, but also made improving education a top priority to encourage investment and create jobs for a youthful population of 260 million people.
Airlangga Hartarto, the current industry minister and chairman of political party Golkar, was among a string of potential candidates meeting the president at the palace.
He said he had discussed how to narrow Indonesia's trade deficit, without elaborating on any role. He has been linked in media to the job of coordinating minister for economic affairs.
Widodo has previously said respected finance minister Sri Mulyani Indrawati would retain a position in the cabinet, but gave no further details.
Additional reporting by Tabita Diela, Jessica Damiana and Stanley Widianto; Writing by Gayatri Suroyo and Ed Davies; Editing by Raju Gopalakrishnan and Alex Richardson