LIMA: Peru's stock index rose almost 5% on Friday morning, after a poll showed a technical tie ahead of June 6's presidential runoff election between leftist candidate Pedro Castillo and right-wing Keiko Fujimori.

Support for Castillo, an elementary school teacher seeking to implement new taxes and royalties on the mining sector, fell 3.3% to 42.6% according to the poll carried out by Datum, compared with a week ago.

Support for Fujimori, the daughter of jailed ex-president Alberto Fujimori, rose 1.6% to 41.7%, the poll showed.

The poll had a 2.8% error margin.

While Castillo has been leading the polls so far, Friday's poll shows the narrowest gap yet.

Castillo has his largest lead with Peru's poor, while Fujimori has majority support in the capital Lima, which accounts for a third of the country's population.

Peru's currency, the sol, rose 1.5% to just under 3.80 soles to the dollar after falling to an all-time low on Wednesday.