LONDON — Announcement of a contract award to MBDA to build a laser-directed energy weapon demonstrator for the British Ministry of Defence (MoD) has been held up by a protest filed by one of the losing bidders.

Thales UK filed the protest after missile-maker MBDA was selected in mid-July for the sought-after contract put up for competition by the MoD's Defence Science and Technology Laboratory (Dstl), according to a source familiar with the program.

The grounds for the protest are unknown at this stage.

Dstl declined to comment on whether MBDA had been selected or whether the decision had resulted in a protest.

"We are still in the process of finalizing the contract. For reasons of commercial confidentiality we do not discuss details of any discussions with the tenderers," a Dstl spokesman said.

Both MBDA and Thales UK declined to comment.

Thales UK took advantage of European procurement laws, which require a 10-day cooling off period between when the MoD informs bidders of its contract award decision and when the final conclusion of the contract is announced, during which time losing suppliers can challenge the decision. Some procurements are exempt from the law.

Defense News reported July 10 that MBDA had been selected and would be confirmed as the winner within days subject to there being no protests from rival companies.

MBDA leads a consortium of companies known as Dragonfire. BAE Systems, Leonardo-Finmeccania, Marshall Defence and Aerospace, and Qinetiq are also among the consortium members.

A Babcock-Raytheon team, Lockheed Martin, Rheinmetall, and Thales UK  are thought to have been among the rival bidders vying to build a solid-state, high-power demonstrator weapon as part of the Dstl's laser-directed energy weapons capability project.

In May, Raytheon executives said the British could conduct land trials on the demonstrator as early as 2018.

Adm. George Zambellas, then-head of the British Royal Navy, told an audience at the DSEI arms exhibition in London last year that the service planned to test the prototype on a warship by the end of the decade.

The demonstration work could eventually lead to the Royal Navy and other services fielding a directed energy weapon.

By contrast, the US deployed the amphibious transport dock Ponce to the Arabian Gulf in 2014 with a laser capable of taking on drones and small surface vessels.

Germany has also invested in the technology with Rheinmetall and MBDA Deutschland, successfully field testing land-based systems.

Industry executives in the UK say the demonstrator program is part of a catch-up effort on laser weapons by the British after the government neglected the sector for more than a decade having developed a laser dazzle capability for warships as far back as 1982.

The Dstl tender document gave the contract value in the range of £20 million to £100 million (US $27 million to $133 million).

Lack of funding prompted Thales UK to tell reporters during a briefing in 2013 it was looking overseas for investment to continue long-term work it had been doing in the sector.