* Aspex criticises CEO's strategy and operational

performance

* Delivery Hero acknowledges letter, continues strategic

review

* Aspex urges 'competitive' asset sales

(Adds details, background from paragraph 6)

FRANKFURT, March 24 (Reuters) - Aspex, a major Delivery

Hero shareholder, on Tuesday urged the online takeaway

group's supervisory board to oust the CEO and his top management

team, escalating the investor's push for a strategic overhaul.

"Wholesale changes in the management team will be required

to address issues faced by the company," Aspex Management said

in a letter to Delivery Hero Chair Kristin Skogen Lund and other

members of the non-executive supervisory board, seen by Reuters.

"Fellow shareholders share our view that (CEO) Niklas Oestberg's

strategy is flawed, and that Delivery Hero's operational

underperformance against peers is accelerating," it said, adding

that the company had suffered from compliance and control

failures.

Delivery Hero acknowledged the letter from Aspex.

"We are progressing with the strategic review and it remains an

ongoing core focus of both the Management and Supervisory

Board," it said in a statement.

The direct call for Oestberg's removal marks an escalation after

Aspex wrote to him earlier this month, warning his job could be

at risk without faster progress in the review.

On Tuesday, Delivery Hero agreed to sell its Foodpanda delivery

business in Taiwan to ride-hailing and delivery firm Grab

for $600 million in cash, which Oestberg called "a key

first step" in the review.

Aspex said the deal terms showed the business's value had been

"significantly eroded".

"This stresses the urgency by which further assets must be

divested in competitive sales processes to prevent further

destruction of shareholder value," it added.