Vladimir Putin addresses supporters celebrating the fourth anniversary of Russia's annexation of Crimea.
CNN  — 

As tensions continued to rise between Moscow and London on Wednesday over the spy poisoning scandal, Russian President Vladimir Putin turned his attention to domestic affairs by visiting Crimea ahead of Sunday’s presidential election.

Putin, who is widely expected to secure a second consecutive term in power, addressed crowds in Sevastopol, highlighting the triumph of Russia’s 2014 annexation of Crimea.

Sunday will mark four years since Russia annexed Crimea from Ukraine, or as Putin told the rally, four years since “Crimea returned home.”

Putin supporters gather for a rally  at Sevastopol's Nakhimov Square.

Russia’s annexation of Crimea from Ukraine triggered crippling international sanctions on the country and has been at the center of Russia-Europe tension.

But speaking after visiting construction workers building a bridge that will link Crimea to mainland Russia, vastly improving transport links to the region, Putin vowed to raise living standards and help those in poverty.

Putin inspects the Crimean Bridge over the Kerch Strait.

The 19 kilometer road-and-rail bridge across the Kerch Strait is expected to open on May 9, the anniversary of the Soviet Union’s victory over Nazi Germany in World War II, Reuters reported.

“We still have a lot to do for the development of Sevastopol and Crimea in general,” Putin said.

“These are long-term projects, but we are working on them, we will be doing them and will implement them for sure. When we are together we are a great force capable of solving the hardest tasks.”

Ukrainian President Petro Poroshenko called Putin’s visit to Crimea “a dangerous provocation.”

In a statement issued by his press office, Poroshenko called on all European partners and the world to react decisively to “the election farce Moscow is organizing this Sunday in the occupied territory of the Ukrainian Crimea – on the fourth anniversary of the attempt to annex the Crimean peninsula.”