Mocha with Typescript - Error [ERR_UNSUPPORTED_DIR_IMPORT]

I get this error when I run mocha tests.

Error [ERR_UNSUPPORTED_DIR_IMPORT]: Directory import '/node_modules/ts-node/register' is not supported resolving ES modules imported from /node_modules/mocha/lib/esm-utils.js

Following is the mocha config file. I am using Node v12. Mocha v9.0.1,

mocharc.json

{
  "extension": ["ts"],
  "spec": "test/lib/**/*.test.ts",
  "require": "ts-node/register",
  "delay": true,
  "bail": true,
  "watch": true
}