import type { ISO639_1LanguageCode } from './locales.js';
/**
 * Determines if a given locale corresponds to a right-to-left (RTL) language.
 *
 * @param language - The `ISO 639-1` language code to check.
 * @returns `true` if the locale is RTL, `false` otherwise.
 */
export declare function isRtlLanguage(language: ISO639_1LanguageCode | undefined): boolean;