The Soviet leadership at first tried to stop or limit the impact of Dubček's initiatives through a series of negotiations.
the Czechoslovak and Soviet Presidiums agreed to bilateral meeting to be held in July 1968 at Čierna nad Tisou, near the Slovak-Soviet border.
The meeting was the first time the Soviet Presidium met outside Soviet territory.

At the meeting, with attendance of Brezhnev, Alexei Kosygin, Nikolai Podgorny, Mikhail Suslov and others on the Soviet side and Dubček, Ludvík Svoboda, Oldřich Černík, Josef Smrkovský and others on the Czechoslovak side, Dubček defended the program of the reformist wing of the KSČ while pledging commitment to the Warsaw Pact and Comecon.
The KSČ leadership, however, was divided between vigorous reformers (Josef Smrkovský, Oldřich Černík, Josef Špaček and František Kriegel) who supported Dubček, and conservatives (Vasil Biľak, Drahomír Kolder, and Oldřich Švestka) who represented an anti-reformist stance.
Brezhnev decided on compromise.
The KSČ delegates reaffirmed their loyalty to the Warsaw Pact and promised to curb "anti-socialist" tendencies, prevent the revival of the Czechoslovak Social Democratic Party, and control the press by the re-imposition of a higher level of censorship.
In return the USSR agreed to withdraw their troops (still stationed in Czechoslovakia since the June 1968 maneuvers) and permit 9 September party congress.
Dubček appeared on television shortly afterwards reaffirming Czechoslovakia's alliance with the Soviet Union and the Warsaw Pact.

On 3 August, representatives from the Soviet Union, East Germany, People's Republic of Poland, Hungary, Bulgaria, and Czechoslovakia met in Bratislava and signed the Bratislava Declaration.
The declaration affirmed unshakable fidelity to Marxism-Leninism and proletarian internationalism and declared an implacable struggle against bourgeois ideology and all "antisocialist" forces.
The Soviet Union expressed its intention to intervene in a Warsaw Pact country if a bourgeois system – a pluralist system of several political parties representing different factions of the capitalist class – was ever established.
After the Bratislava conference, Soviet troops left Czechoslovak territory but remained along Czechoslovak borders.

As these talks proved unsatisfactory, the USSR began to consider a military alternative.
The Soviet Union's policy of compelling the socialist governments of its satellite states to subordinate their national interests to those of the Eastern Bloc (through military force if needed) became known as the Brezhnev Doctrine.
The Soviet leadership at first tried to stop or limit the impact of Dubček's initiatives through a series of negotiations. the Czechoslovak and Soviet Presidiums agreed to bilateral meeting to be held in July 1968 at Čierna nad Tisou, near the Slovak-Soviet border. The meeting was the first time the Soviet Presidium met outside Soviet territory.
At the meeting, with attendance of Brezhnev, Alexei Kosygin, Nikolai Podgorny, Mikhail Suslov and others on the Soviet side and Dubček, Ludvík Svoboda, Oldřich Černík, Josef Smrkovský and others on the Czechoslovak side, Dubček defended the program of the reformist wing of the KSČ while pledging commitment to the Warsaw Pact and Comecon. The KSČ leadership, however, was divided between vigorous reformers (Josef Smrkovský, Oldřich Černík, Josef Špaček and František Kriegel) who supported Dubček, and conservatives (Vasil Biľak, Drahomír Kolder, and Oldřich Švestka) who represented an anti-reformist stance. Brezhnev decided on compromise. The KSČ delegates reaffirmed their loyalty to the Warsaw Pact and promised to curb "anti-socialist" tendencies, prevent the revival of the Czechoslovak Social Democratic Party, and control the press by the re-imposition of a higher level of censorship. In return the USSR agreed to withdraw their troops (still stationed in Czechoslovakia since the June 1968 maneuvers) and permit 9 September party congress. Dubček appeared on television shortly afterwards reaffirming Czechoslovakia's alliance with the Soviet Union and the Warsaw Pact.
On 3 August, representatives from the Soviet Union, East Germany, People's Republic of Poland, Hungary, Bulgaria, and Czechoslovakia met in Bratislava and signed the Bratislava Declaration. The declaration affirmed unshakable fidelity to Marxism-Leninism and proletarian internationalism and declared an implacable struggle against bourgeois ideology and all "antisocialist" forces. The Soviet Union expressed its intention to intervene in a Warsaw Pact country if a bourgeois system – a pluralist system of several political parties representing different factions of the capitalist class – was ever established. After the Bratislava conference, Soviet troops left Czechoslovak territory but remained along Czechoslovak borders.
As these talks proved unsatisfactory, the USSR began to consider a military alternative. The Soviet Union's policy of compelling the socialist governments of its satellite states to subordinate their national interests to those of the Eastern Bloc (through military force if needed) became known as the Brezhnev Doctrine.
Warsaw Pact invasion of Czechoslovakia