Ever since the annexation of Crimea in 2014, the list of sanctions on Russia has piled up.

Many of these have been imposed by the US and the EU and some could be watered down or repealed as part of a proposed meeting between Donald Trump and the Russian president Vladimir Putin.

The G20 summit in Hamburg on the 7-8 July is expected to be the first time that the pair will sit down one on one after months of debates, discussions and investigations into links between Trump's election campaign and Moscow.

Sanctions increased in 2016 in the wake of the alleged Russian hacking on the DNC and attempts to intervene in the presidential election.

These sanctions have included the closure of diplomatic compounds in the US as well as the freezing of assets belonging to Russian businessmen, particularly those close to the Kremlin.

Responding to the 2016 election interference, Barack Obama ordered the closure of two diplomatic compounds as well as the expulsion of officials.

According to officials close to Trump, it is thought that the reopening of these facilities, in Maryland and New York, could be used as bargaining chips with Putin, though what the US would get in return is unknown.

Trump has signalled in the past that sanctions could be eased. However, with no sign of let-up in Russia's military intervention in Ukraine as well as the continuing raft of investigations into Trump's ties to Russia, easing sanctions is a sensitive topic.

However, Trump is in a minority in Washington. On 14 June, the Senate overwhelmingly voted to impose further sanctions on Russia by a vote of 98-2. The push to strengthen penalties on Russia has been delayed as some GOP members in the House attempt to water down some of the language in the 140-page bill.

Secretary of State Rex Tillerson had attempted to improve relations between the two nations, but was stung when photos of a White House meeting with his Russian counterpart Sergey Lavrov were released by the Russian press, despite an agreement not to have them publicised.

This then came as Trump revealed classified information regarding military operations in Syria with Lavrov and the ambassador to the US, Sergey Kislyak.

Since then, Tillerson has moved against any relaxation in sanctions.

On Capitol Hill, Russia and Putin are on most people's lips, both Democrat and Republicans.

A series of investigations by the FBI, congressional committees and the DOJ have been the main talking point ever since the 2016 election, and these have ramped up in recent months.

The DOJ, now guided by a special counsel, is looking into the ties between the Trump campaign, Russia and any possible cover-up.

The senate intelligence committees are investigating possible Russian interventions into the 2016 election.

The Senate Judiciary Committee and House Oversight and Government Reform Committee are looking into former national security adviser Michael Flynn as well as the firing of former FBI chief James Comey.

Despite the departure of Comey, who believed that he was fired because of the FBI investigation into Trump's ties to Russia, the bureau is continuing to dig deeper into and possible collusion.