However, as the relations between the Western Allies and the Soviet Union soured and the Cold War began, the joint administration of Germany and Berlin broke down.

[5] The Volkspolizei and Soviet military personnel also continued the process of blocking all the roads leading away from the city, resulting in several armed standoffs and at least one skirmish with the French Gendarmerie and the Bundesgrenzschutz that June.

We interpret the effect of Articles 23 and 144 (2) of the Basic Law as constituting acceptance of our previous request that while Berlin may not be accorded voting membership in the Bundestag or Bundesrat nor be governed by the Federation she may, nevertheless, designate a small number of representatives to the meetings of those legislative bodies.

All legislation of the House of Representatives, whether of the West Berlin legislature or adopted federal law, only applied under the proviso of confirmation by the three Western Allied commanders-in-chief.

The Governing Mayor and Senators (ministers) had to be approved by the Western Allies and thus derived their authority from the occupying forces, not from their electoral mandate.

This move was, however, not recognised by the Western Allies, who continued to view all of Berlin as a jointly occupied territory belonging to neither of the two German states.

These differed visually from the regular West German identity cards, with green bindings instead of the grey standard, they did not show the "Federal Eagle" or coat of arms, and contained no indications as to the issuing State.

As many immigrants from East Germany did not intend to stay in Berlin[citation needed], flights – the only option for those people to reach West Germany without coming into contact with East German authorities – were subsidized by the West German government despite being operated only by companies registered in and owned by nationals of the western occupying powers.

[33] NATO also took an increased interest in the specific issue related to West Berlin, and drafted plans to ensure to defend the city against an eventual attack from the East.

The resulting borderline was further complicated with a lot of geographical oddities, including a number of exclaves and enclaves that Greater Berlin had inside some neighbouring municipalities since 1920, all of which happened to become part of the British or American sectors after 1945, so that parts of West Berlin came to be surrounded by East Germany Furthermore, the Gatow/Staaken exchange in August 1945 resulted in the geographically western half of Berlin-Staaken, which was located in the western outskirts of the city, becoming de jure Soviet occupied.

A valid passport was required for citizens of West Germany and other western nationals to be produced at East German border checks.

For journeys between West Berlin and Poland or Czechoslovakia through East Germany, each traveller was also required to present a valid visa for the destination country.

Since such meetings were deemed illegal by the East German government, border guards would calculate the travel duration from the time of entry and exit of the transit route.

On 30 March 1955, East Germany raised the toll for passenger cars to 30 Deutsche Marks, but after West German protests, in June of the same year, it changed it back to the previous rate.

[citation needed] The legal necessity of keeping the term 'Deutsche Reichsbahn' explains the surprising use of the word 'Reich' (with its Imperial and Nazi connotations) in the name of an official organisation of the communist GDR.

Two waterways via the rivers and canals Havel and Mittellandkanal were open for inland navigation, but only freight vessels were allowed to cross from West Berlin into East German waters.

[57] The western entrance to the Teltowkanal, connecting several industrial areas of West Berlin for heavy freight transport, was blocked by East Germany in Potsdam-Klein Glienicke.

[citation needed] The airspace controlled by the Berlin Air Safety Center comprised a radius of 32 km (20 mi) around the seat of the center in the Kammergericht building in Berlin-Schöneberg – thus covering most of East and West Berlin and the three corridors, of the same width – one northwestwards to Hamburg (Fuhlsbüttel Airport), one westwards to Hanover, and one southwestwards to Frankfurt upon Main (Rhein-Main Air Base).

Until 1961, East Germany occasionally issued permits to West Berliners to visit the cemeteries on the Catholic feast of All Saints on 1 November and on the Protestant Day of Repentance and Prayer.

Rail traffic between East and West Berlin was sharply reduced and restricted to a small number of checkpoints under GDR control.

[citation needed] Following the policy of détente of the Federal Government under Chancellor Willy Brandt, West Berliners could again apply for visas to visit East Germany, which were granted more freely than in the period until 1961.

Instead of changing the Western rules, so that the Easterly intended interruption of the cross-border tram traffic would not happen, the BVG (West) insisted on male drivers.

All Eastern streets, bridges, paths, windows, doors, gates, and sewers opening to West Berlin were systematically sealed off by walls, concrete barriers, barbed wire, and/or bars.

On 14 August, under the pretext that Western demonstrations necessitated it, the East closed the checkpoint at the Brandenburg Gate 'until further notice', a situation that was to last until 22 December 1989, when it was finally reopened.

According to the specified regulations valid from 2 November on Eastern pensioners could apply and were usually allowed, to travel into the West to visit relatives once a year for a maximum of four weeks.

[citation needed] The situation only changed fundamentally after 11 December 1971 when, representing the two German states, Egon Bahr from the West and Michael Kohl from the East signed the Transit Agreement.

A shed formerly housing one such Büro für Besuchs- und Reiseangelegenheiten can be found on Waterlooufer 5–7 in Berlin-Kreuzberg, close to Hallesches Tor underground station.

After the construction of the Wall, ridership fell so much that running the S-Bahn lines in West Berlin turned into a loss-making exercise: wages and maintenance – however badly it was carried out – cost more than income from ticket sales.

Eastern controls were slowly eased into spot checks and finally abolished on 30 June 1990, the day East and West introduced the union concerning currency, economy and social security (German: Währungs-, Wirtschafts- und Sozialunion).

Passengers could change there between U 6, S 2 and the elevated S 3 (then starting and ending in Friedrichstraße) or for the transit trains to West Germany, buy duty-free tobacco and liquor for Western marks in GDR-run Intershop kiosks, or enter East Berlin through a checkpoint right in the station.