Zlatan Ibrahimovic squared up to Romelu Lukaku in Tuesday's all-Milan Italian Cup quarter-final, riling his former Manchester United teammate by evoking voodism and calling him "a little donkey", according to reports on Wednesday.

AC Milan forward Ibrahimovic and his Inter Milan opponent Lukaku were involved in a heated altercation at the half-time whistle in the San Siro.

Ibrahimovic taunted Lukaku and infuriated the Belgian by laughing in his face before the pair went head-to-head.

"Go to your voodoo shit, you little donkey," Ibrahimovic told Lukaku in English, alluding to an episode during Lukaku's time at Everton.

In 2018 Everton's majority shareholder Farhad Moshiri suggested Lukaku had declined a new Everton contract after heeding the advice of a voodoo message.

Lukaku, who in 2017 had joined Manchester United, rejected outright any notion of voodism influencing his decision to leave Everton.

In an interview with the BBC in January 2018, a representative of the player raised the possibility of taking legal action against Moshiri, pointing out Lukaku was in fact Catholic.

On Tuesday, Ibrahimovic and Lukaku continued to trade insults as they headed towards the tunnel with a furious Lukaku being restrained by his teammates.

Both players were booked over the incident.

Ibrahimovic was subsequently sent off after picking up a second yellow card 15 minutes after the break for bringing down Aleksandar Kolarov.

Christian Eriksen scored a last-gasp winner to send Inter into the semi-finals after goals by both Lukaku and Ibrahimovic.

Milan manager Stefano Pioli and his inter counterpart Antonio Conte played down the row, saying they had not heard the players' arguing and blamed any tension on the nature of the fixture as a Milan derby.

But Italian daily La Repubblica said the clash was "a poor spectacle that spoilt a great game" while Corriere della Sera said it was a case of "one goal each, (but) a bad scenario for everyone". Corriere dello Sport called it a "shameful" episode.

According to Milan sports daily Gazzetta dello Sport Ibrahimovic apologised to his team for getting sent off but denied using racist terms towards Lukaku.