Mr. Mark Wall reports

MOUNTAIN PROVINCE DIAMONDS RETURNS 40-METRE KIMBERLITE INTERCEPT, 40 METRES FROM KNOWN TUZO RESOURCE, POSITIVE DRILLING RESULTS FROM THE HEARNE KIMBERLITE AT THE GAHCHO KUE MINE

Mountain Province Diamonds Inc. has discovered an additional kimberlite, approximately 40 metres to the northeast of the modelled Tuzo kimberlite. In addition, the drilling of the Hearne Deep and the Northwest Extension has seen multiple intercepts of up to 287 metres of kimberlite.

The Hearne Northwest Extension was identified in late 2021, when a kimberlite exposure (25 metres across) was encountered in a lower bench face during routine mining operations. Drilling programs in 2022 indicated that a significant volume of previously unknown kimberlite could exist, with 10 of 16 drill holes reporting kimberlite intersections up to 114 metres in the extension (see news releases dated July 18 and Nov. 30, 2022). In the 2023 program, 10 of 11 drill holes collared within and outside of the Hearne pit have intersected kimberlite with the longest intersection being 287 metres.

Mark Wall, the company's president and chief executive officer, commented: "These latest results at Hearne confirm that a significant volume of kimberlite exists in the Northwest Extension. Combined with our earlier results, we now have 21 drill holes that define the extension below the final pit and to the northwest. We are actively engaged with our operating partner De Beers to look at ways to recover this deeper kimberlite by underground mining."

In the present program, seven drill holes were collared outside of the pit, and four were collared on kimberlite within the pit to test the width and depth of the extension, respectively. A summary of the latest drilling results is provided herein.

Following on the discovery and delineation of the Hearne Northwest Extension, drilling to look for a similar extension has been started at Tuzo. Limited historical drilling at Tuzo has confirmed kimberlite to a vertical depth of over 700 metres.

Based on the northeast-directed downward ramping of the 5034 kimberlite and its proximity to Tuzo, a single drill hole was collared east of Tuzo to test for a northeast extension.

Drill hole MPV-23-632C intersected TKt/HKt kimberlite from 669.77 to 710.00 metres, and is located roughly 40 metres northeast of the Tuzo kimberlite. The kimberlite phase in Tuzo that is nearest to the intersect is modelled also as TKt. Logging and mineral chemistry of the drill core are under way to confirm whether it is similar in detail to Tuzo.

Mr. Wall commented: "While the drilling for Tuzo is early stage and is still under way, we are encouraged by the width of the kimberlite intersection and its similarities to Tuzo based on initial logging. We and our partner De Beers will consider further drilling if the detailed work on this hole continues to return positive results."

About Mountain Province Diamonds Inc.

Mountain Province is a 49-per-cent participant with De Beers Canada in the Gahcho Kue diamond mine located in Canada's Northwest Territories. The Gahcho Kue joint venture consists of several kimberlites that are actively being mined, developed and explored for future development. The company also controls over 113,000 hectares of highly prospective mineral claims and leases surrounding the Gahcho Kue mine that include an indicated mineral resource for the Kelvin kimberlite and inferred mineral resources for the Faraday kimberlites. Kelvin is estimated to contain 13.62 million carats (Mct) in 8.50 million tonnes (Mt) at a grade of 1.60 carats per tonne and a value of $63 (U.S.) per carat. Faraday 2 is estimated to contain 5.45 Mct in 2.07 Mt at a grade of 2.63 carats per tonne and a value of $140 (U.S.) per ct. Faraday 1-3 is estimated to contain 1.90 Mct in 1.87 Mt at a grade of 1.04 carats per tonne and a value of $75 (U.S.) per carat. All resource estimations are based on a one-millimetre diamond size bottom cut-off.

Qualified persons

The disclosure in this news release of scientific and technical information regarding Mountain Province's mineral properties has been reviewed and approved by Matthew MacPhail, PEng, MBA, and Tom E. McCandless, PhD, PGeo, both employees of Mountain Province and qualified persons as defined by National Instrument 43-101 (Standards of Disclosure for Mineral Projects).

We seek Safe Harbor.