import { ImpersonationResponse } from './types';
export declare function getGceMetadataToken(metadataServerUrl?: string): Promise<string>;
export declare function impersonateServiceAccount(sourceToken: string, targetServiceAccount: string, scopes: string[], delegates?: string[], lifetime?: string): Promise<ImpersonationResponse>;
export declare function parseScopesString(scopesString: string): string[];
export declare function parseDelegatesString(delegatesString?: string): string[] | undefined;