(Reuters) - U.S. health insurer Anthem Inc (>> Anthem Inc) said on Friday it will exit Obamacare markets in Virginia and reduce its plan offerings in Washington and Scott counties and the city of Bristol next year.

The move comes nearly two weeks after President Donald Trump took aim at insurers by threatening to cut the healthcare subsidy payments that make Obamacare plans affordable, after repeatedly failing in his efforts to dismantle former President Barack Obama's healthcare law.

Insurers are facing an upheaval in their health insurance businesses due to uncertainty over the healthcare legislation as Republican lawmakers seek to follow through on their promise to repeal and replace the Affordable Care Act.

Health insurers, such as UnitedHealth Group Inc (>> UnitedHealth Group), Aetna Inc (>> Aetna Inc) and Humana Inc (>> Humana Inc), have also exited most of the states where they used to sell plans.

The insurers have asked the government to commit to making the $8 billion in subsidy payments for 2018, saying they may raise rates or leave the individual insurance marketplace if there is too much uncertainty.

On Monday, Anthem said it would no longer offer Obamacare plans in Nevada's state exchange and half of Georgia's counties in 2018.

The company said on Friday it will only offer off-exchange plans in Washington and Scott counties and the city of Bristol.

Hundreds of U.S. counties are at risk of losing access to private health coverage in 2018 as health insurers consider pulling out of those markets in the coming months.

Last week, Molina Healthcare Inc (>> Molina Healthcare, Inc.) said it would stop selling Obamacare plans in Utah and Wisconsin.

(Reporting by Divya Grover in Bengaluru; Editing by Shounak Dasgupta)