Vladimir Putin 2

Prime Minister Theresa May and Russian President Vladimir Putin have vowed to improve the relationship between the two countries after speaking for the first time since Ms May took office.

Downing Street confirmed that the two leaders spoke for the first time on the phone on Tuesday, with the Kremlin saying Ms May and President Putin both expressed how disappointed they were with current relations.

They will meet for the first time at the G20 summit in China next month.

One particular area where Ms May and President Putin pledged co-operation was on aviation security. There have been several instances of Russian military aircraft flying perilously close to British air space over the past year or so. But the pair agreed that co-operation was vital in combatting the threat of terrorism.

A Downing Street spokesperson said: "The prime minister noted the importance of the relationship between the UK and Russia and expressed the hope that, despite differences on certain issues, they could communicate in an open and honest way about the issues that mattered most to them.

"The prime minister and president agreed that British and Russian citizens faced common threats from terrorism, and that co-operation on aviation security in particular was a vital part of the international counter-terrorism effort."

The relationship between the two countries has been somewhat strained since 2006, when a British inquiry into the death of Russian spy Alexander Litvinenko reported that President Putin "probably" authorised his assassination. Since then, there has been further tension over Russia's support for the Syrian President Bashar al-Assad and the invasion of Ukraine in 2014.

The UK led calls for economic sanctions against Russia made by the US and EU as punishment for its part in the annexation of the Crimea region of Ukraine. The Russian government consistently denied direct involvement in the invasion, but it is widely believed that pro-Russian separatist troops were supported by the Russian military.

In 2015, official figures showed that the Russian economy contracted by 3.7%. It suffered a double blow as the economic sanctions were coupled with plunging oil prices, upon which the economy is heavily reliant. The government had formed its budget based on oil prices of $82 per barrel, but prices spent much of 2015 closer to $40 per barrel.

In June, the European Union agreed to extend those sanctions until at least the end of January 2017. However, many European politicians are calling for a softer approach to Russia's punishment.