Circular definition of import alias 'theme'

I am trying to extend the theme of a third party private npm module. The project compiles successfully but I keep getting a typescript error Circular definition of import alias 'externalTheme'

Below is how I am extending the theme. This is working perfectly in the way that it is using both my theme and the external theme combined

import { externalTheme, ExternalThemeInterface } from 'external-npm-repo...'

import { colors, ColorsTypes } from './colors'

export const MyTheme: MyThemeInterface = {
    ...theme,
    colors,
}

export interface MyThemeInterface extends ExternalThemeInterface {
    colors: ColorsTypes
}

The error I am getting is referencing circular dependency with the externalTheme import, im not sure what this exactly means and havent found any clear references when researching.

These are my Typescript settings

        "allowJs": true,
        "alwaysStrict": true,
        "esModuleInterop": true,
        "forceConsistentCasingInFileNames": true,
        "isolatedModules": true,
        "jsx": "preserve",
        "lib": ["dom", "es2017"],
        "module": "esnext",
        "moduleResolution": "node",
        "noEmit": true,
        "noFallthroughCasesInSwitch": true,
        "noUnusedLocals": true,
        "noUnusedParameters": true,
        "resolveJsonModule": true,
        "skipLibCheck": true,
        "strict": true,
        "target": "esnext"

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