DPS is asking why the ruling majority will not send regional development minister and deputy prime minister Galab Donev to parliament to answer for the rising cost of guardrail contracts. DPS MP Halil Letifov told reporters at the National Assembly.

The row follows remarks by regional minister Ivan Shishkov. He says annexes to some of the contracts push the price more than 50% above the limit that public procurement rules allow.

"A moment ago we heard confirmation that costs have gone up, that there is a 'magic formula', and that this magic formula in fact raises the price of these guardrails by up to 160%," Letifov said.

He said money is being stolen through the guardrails, and that experts compare them to pretzel sticks. Letifov said this directly threatens the health and lives of all citizens and road users.

The MP also said: "We cannot understand why the minister is hiding, including from the majority – the minister of regional development and public works and deputy prime minister Galab Donev."

Letifov insists that Donev come to the National Assembly, because he owes answers there and is subject to its oversight. He said the deputy prime minister must answer all questions and doubts about corrupt practices, which DPS has reported to the authorities.

DPS has filed complaints with the prosecutor's office about specific contracts where guardrail prices rose. The complaints also cover contracts based on the so-called "magic formula".