diff --git a/packages/angular/cli/models/architect-command.ts b/packages/angular/cli/models/architect-command.ts
index 5871bd0ccb69..ee1df7dc085e 100644
--- a/packages/angular/cli/models/architect-command.ts
+++ b/packages/angular/cli/models/architect-command.ts
@@ -9,7 +9,6 @@ import { Architect, Target } from '@angular-devkit/architect';
 import { WorkspaceNodeModulesArchitectHost } from '@angular-devkit/architect/node';
 import { experimental, json, schema, tags } from '@angular-devkit/core';
 import { NodeJsSyncHost } from '@angular-devkit/core/node';
-import { Version } from '../upgrade/version';
 import { BepJsonWriter } from '../utilities/bep';
 import { parseJsonSchemaToOptions } from '../utilities/json-schema';
 import { isPackageNameSafeForAnalytics } from './analytics';
@@ -275,9 +274,6 @@ export abstract class ArchitectCommand<
   protected async runArchitectTarget(
     options: ArchitectCommandOptions & Arguments,
   ): Promise<number> {
-    // Check Angular version.
-    Version.assertCompatibleAngularVersion(this.workspace.root);
-
     const extra = options['--'] || [];
 
     try {
diff --git a/packages/angular/cli/upgrade/version.ts b/packages/angular/cli/upgrade/version.ts
deleted file mode 100644
index 774678663b99..000000000000
--- a/packages/angular/cli/upgrade/version.ts
+++ /dev/null
@@ -1,135 +0,0 @@
-/**
- * @license
- * Copyright Google Inc. All Rights Reserved.
- *
- * Use of this source code is governed by an MIT-style license that can be
- * found in the LICENSE file at https://angular.io/license
- */
-
-import { tags, terminal } from '@angular-devkit/core';
-import * as path from 'path';
-import { SemVer, satisfies } from 'semver';
-
-
-export class Version {
-  private _semver: SemVer | null = null;
-  constructor(private _version: string | null = null) {
-    this._semver = _version ? new SemVer(_version) : null;
-  }
-
-  isAlpha() { return this.qualifier == 'alpha'; }
-  isBeta() { return this.qualifier == 'beta'; }
-  isReleaseCandidate() { return this.qualifier == 'rc'; }
-  isKnown() { return this._version !== null; }
-
-  isLocal() { return this.isKnown() && this._version && path.isAbsolute(this._version); }
-  isGreaterThanOrEqualTo(other: SemVer) {
-    return this._semver !== null && this._semver.compare(other) >= 0;
-  }
-  satisfies(other: string) {
-    // This comparison includes pre-releases (like betas and rcs), and considers them to be
-    // before the release proper.
-    // e.g. '9.0.0-beta.1' will satisfy '>=7.0.0 <9.0.0', but '9.0.0' will not.
-    return this._semver !== null && satisfies(this._semver, other, { includePrerelease: true });
-  }
-
-  get major() { return this._semver ? this._semver.major : 0; }
-  get minor() { return this._semver ? this._semver.minor : 0; }
-  get patch() { return this._semver ? this._semver.patch : 0; }
-  get qualifier() { return this._semver ? this._semver.prerelease[0] : ''; }
-  get extra() { return this._semver ? this._semver.prerelease[1] : ''; }
-
-  toString() { return this._version; }
-
-  static assertCompatibleAngularVersion(projectRoot: string) {
-    let angularCliPkgJson;
-    let angularPkgJson;
-    let rxjsPkgJson;
-    const resolveOptions = { paths: [projectRoot] };
-
-    try {
-      const angularPackagePath = require.resolve('@angular/core/package.json', resolveOptions);
-      const rxjsPackagePath = require.resolve('rxjs/package.json', resolveOptions);
-
-      angularPkgJson = require(angularPackagePath);
-      rxjsPkgJson = require(rxjsPackagePath);
-    } catch {
-      console.error(terminal.bold(terminal.red(tags.stripIndents`
-        You seem to not be depending on "@angular/core" and/or "rxjs". This is an error.
-      `)));
-      process.exit(2);
-    }
-
-    if (!(angularPkgJson && angularPkgJson['version'] && rxjsPkgJson && rxjsPkgJson['version'])) {
-      console.error(terminal.bold(terminal.red(tags.stripIndents`
-        Cannot determine versions of "@angular/core" and/or "rxjs".
-        This likely means your local installation is broken. Please reinstall your packages.
-      `)));
-      process.exit(2);
-    }
-
-    try {
-      const angularCliPkgPath = require.resolve('@angular/cli/package.json', resolveOptions);
-      angularCliPkgJson = require(angularCliPkgPath);
-      if (!(angularCliPkgJson && angularCliPkgJson['version'])) {
-        throw new Error();
-      }
-    } catch (error) {
-      console.error(terminal.bold(terminal.red(tags.stripIndents`
-        Cannot determine versions of "@angular/cli".
-        This likely means your local installation is broken. Please reinstall your packages.
-      `)));
-      process.exit(2);
-    }
-
-    const cliMajor = new Version(angularCliPkgJson['version']).major;
-    // e.g. CLI 8.0 supports '>=8.0.0 <9.0.0', including pre-releases (betas, rcs, snapshots)
-    // of both 8 and 9.
-    const supportedAngularSemver = `^${cliMajor}.0.0-beta || ` +
-      `>=${cliMajor}.0.0 <${cliMajor + 1}.0.0`;
-
-    const angularVersion = new Version(angularPkgJson['version']);
-    const rxjsVersion = new Version(rxjsPkgJson['version']);
-
-    if (angularVersion.isLocal()) {
-      console.error(terminal.yellow('Using a local version of angular. Proceeding with care...'));
-
-      return;
-    }
-
-    if (!angularVersion.satisfies(supportedAngularSemver)) {
-      console.error(terminal.bold(terminal.red(tags.stripIndents`
-          This version of CLI is only compatible with Angular versions ${supportedAngularSemver},
-          but Angular version ${angularVersion} was found instead.
-
-          Please visit the link below to find instructions on how to update Angular.
-          https://angular-update-guide.firebaseapp.com/
-        ` + '\n')));
-      process.exit(3);
-    } else if (
-      angularVersion.isGreaterThanOrEqualTo(new SemVer('6.0.0-rc.0'))
-      && !rxjsVersion.isGreaterThanOrEqualTo(new SemVer('5.6.0-forward-compat.0'))
-      && !rxjsVersion.isGreaterThanOrEqualTo(new SemVer('6.0.0-beta.0'))
-    ) {
-      console.error(terminal.bold(terminal.red(tags.stripIndents`
-          This project uses version ${rxjsVersion} of RxJs, which is not supported by Angular v6+.
-          The official RxJs version that is supported is 5.6.0-forward-compat.0 and greater.
-
-          Please visit the link below to find instructions on how to update RxJs.
-          https://docs.google.com/document/d/12nlLt71VLKb-z3YaSGzUfx6mJbc34nsMXtByPUN35cg/edit#
-        ` + '\n')));
-      process.exit(3);
-    } else if (
-      angularVersion.isGreaterThanOrEqualTo(new SemVer('6.0.0-rc.0'))
-      && !rxjsVersion.isGreaterThanOrEqualTo(new SemVer('6.0.0-beta.0'))
-    ) {
-      console.warn(terminal.bold(terminal.red(tags.stripIndents`
-          This project uses a temporary compatibility version of RxJs (${rxjsVersion}).
-
-          Please visit the link below to find instructions on how to update RxJs.
-          https://docs.google.com/document/d/12nlLt71VLKb-z3YaSGzUfx6mJbc34nsMXtByPUN35cg/edit#
-        ` + '\n')));
-    }
-  }
-
-}