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By Jorgelina do Rosario and Karin Strohecker

LONDON, May 23 (Reuters) - Asset managers Ashmore and GMO have joined the steering committee of a creditor group of Ghana's international bondholders as the West African country's debt restructuring efforts gather pace, three sources close to the matter said.

Ghana, which is facing its worst economic crisis in a generation, is targeting $10.5 billion of external debt service relief from 2023-2026, according to the International Monetary Fund, which signed off on a $3 billion programme last week.

"Ghana's plan looks pretty ambitious," said one source, who asked not to be named because talks are private. "This government is very keen to get a quick deal."

Ashmore declined to comment. GMO did not immediately respond to a request for comment.

Other members of the steering committee are Abrdn, Amundi, BlackRock, Greylock and Ninety One, according to earlier statements from the group.

Ghana faces a debt overhaul after its already strained finances buckled under the economic fallout from COVID-19 and Russia's invasion of Ukraine, and defaulted on most of its external debt in December.

The nation is also in talks to rework $13.3 billion of debt to private overseas bondholders, according to IMF's latest data.

Of its $30 billion in external debt, $20 billion is eligible for restructuring, including loans by bilateral creditors such as the Paris Club and China. (Reporting by Jorgelina do Rosario and Karin Strohecker; editing by Jason Neely)