Oct 7 (Reuters) - Poland has fined Russia's Gazprom more than $7.6 billion for building the Nord Stream 2 gas pipeline without Warsaw's approval, its watchdog said on Wednesday.

Russia's bid to double its gas export capacity across the Baltic Sea has prompted opposition, including U.S. sanctions, stalling completion of the $11 billion pipeline.

In addition to Europe's increased reliance on Russian gas, opponents are wary of Moscow's motives as the pipeline will allow it to curb gas transit via Ukraine, cutting off a source of revenue for Kiev.

Below is a timeline of Nord Stream 2's development:

2011

November: The Nord Stream 1 twin pipeline across the Baltic Sea opens between Russia and Germany with a capacity of 55 billion cubic metres (bcm), or enough to heat 26 million homes.

Gazprom and Western partners start looking double the project at an estimated cost of 9.5 billion euros ($11.3 billion).

2015

June: Gazprom, Royal Dutch Shell, E.ON, OMV, BASF and ENGIE agree to build Nord Stream 2.

2016

March: Eight EU governments - the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania and Slovakia - object to the project, saying it would have "potentially destabilising geopolitical consequences".

2017

April: Nord Stream 2 AG signs financing agreements with ENGIE, OMV, Shell, E.ON offshoot Uniper, and BASF's subsidiary Wintershall [https://reut.rs/2FgjZZZ ]

2018

January: Germany grants Nord Stream 2 a permit for construction and operation in German waters and landfall areas near Lubmin in Mecklenburg-Vorpommern

September: pipe-laying operations start in the Baltic Sea

2019

January - U.S. ambassador to Germany warns companies involved in the construction could face sanctions [https://bit.ly/2FhqaN3 ]

December - Swiss-Dutch company Allseas suspends its pipe-laying activities in anticipation of U.S. President Donald Trump signing a bill which includes sanctions on firms involved.

The group behind Nord Stream 2 says it aims to complete the pipeline, despite the U.S. sanctions threat.

Trump signs the bill.

2020

January: Russian President Vladimir Putin says he hopes the pipeline will be finished by the end of Q1 2021. German Chancellor Angela Merkel says she believes the project is legitimate under European regulations and should therefore be completed.

May: Germany's energy regulator declines to grant a waiver to operators of the pipeline of EU directives that require separate operators for production, transport and distribution of energy on German territory.

An EU court rejects a challenge to EU gas rules from the operators of the Nord Stream 1 and Nord Stream 2 pipelines, saying it was up to individual members states to enforce them.

August: Poland fines Gazprom 213 million zloty ($57 million) for a lack of cooperation with the country's anti-monopoly office regarding Nord Stream 2.

September 3: Pressure mounts on Merkel to reconsider the pipeline, after she says Kremlin critic Alexei Navalny was poisoned with a Soviet-style nerve agent.

September 11: The premier of the German state of Mecklenburg-Vorpommern, where Nord Stream 2 would come ashore, says the pipeline should not be used to punish Moscow over the Navalny case. Merkel wants to agree a response with EU partners.

October 1: Denmark grants a permit for Nord Stream 2 to operate in its waters.

October 7: Poland fines Gazprom more than $7.6 billion for building the pipeline without approval from its anti-monopoly watchdog.

($1 = 0.8424 euros) (Reporting by Tommy Lund and Bartosz Dabrowski in Gdansk; editing by Jason Neely and Barbara Lewis)